A scientific theory is a well-tested explanation for a widely accepted hypothesis.
What is a scientific theory?A scientific theory is a coherent statement or set of ideas that explains observed facts or phenomena and correctly predicts new facts or phenomena not previously observed, or which sets out the laws and principles of something known or observed.
In summary, a theory is a hypothesis confirmed by observation or experiment.
A body of facts that have been repeatedly confirmed through observation and experiment is said to be a theory.
Learn more about theory at: https://brainly.com/question/17152046
#SPJ1
Calculate the buffer ratio (base/acid) required for a buffer of pH = 5.68 that is prepared by mixing sodium hydrogen oxalate and sodium oxalate. A table of pKa values can be found here. Report your answer to 2 significant figures in scientific notation. Calculate the pH (to two decimal places) of the buffer solution after the addition of 7.77 g of sodium hydrogen carbonate (NaHOCOO) to the buffer solution above. Assume 5% approximation is valid and that the volume of solution does not change.
122.5 grams of oxalic add dihydrate (MW = 126.07 g/mole) and disodium oxalate (MW = 133.99 g/mole) were required to prepare this buffer if the total oxalate concentration is 0.115 M.
Weak acids are defined as acids that don't completely dissociate in solution. It can be explained as any acid that is not a strong acid. The strength of a weak acid depends on how much it gets dissociates and the more it dissociates, the stronger the acid. The mass of the weak acid in a solution of a certain pH can be determined by calculating the original concentration of the acid after calculating the concentration of the hydrogen ions with the help of the pH value of the solution.
The Concentration of oxalate ion is 0.115 M.
pKa1 is 1.250.
pKa2 is 4.266.
pH is 5.193.
Molarity = (mass / molar mass) / 1 / volume in liter
The molar mass is 126.07g/mole.
Mass = Molarity × molar mass × Volume in liter
Mass=0.972 M × 126.07 g/mole × 1.00 L
= 122.5 gram
To learn more about concentration
https://brainly.com/question/17206790
#SPJ4
The complete question is,
A buffer prepared by dissolving oxalic add dihydrate (H2C2O4⋅2H2O) and disodium oxalate (Na2C2O4) in 1.00 L of water has a pH of 5.193. How many grams of oxalic add dihydrate (MW = 126.07 g/mole) and disodium oxalate (MW = 133.99 g/mole) were required to prepare this buffer if the total oxalate concentration is 0.115 M? Oxalic acid has pKa values of 1.250 (pKa1) and 4.266 (pKa2).
which the following optically active alcohol is treated with hbr, a racemic mixture of alkyl bromides is obtained
(S)-2-butanol will undergo an SN2 reaction with HBr to produce a racemic mixture of alkyl bromides. Here option B is the correct answer.
When optically active alcohol is treated with HBr, the reaction follows an SN1 or SN2 mechanism. In the case of SN1, a carbocation intermediate is formed, and in SN2, a backside attack by the nucleophile occurs. The stereochemistry of the product depends on the configuration of the intermediate and the direction of attack.
In the case of (S)-2-butanol, the hydroxyl group is attached to the second carbon atom, which makes it a primary alcohol. When treated with HBr, it undergoes an SN2 reaction, where the hydroxyl group is replaced by the bromine atom. The nucleophile attacks from the backside of the molecule, leading to an inversion of configuration.
This results in the formation of a racemic mixture of alkyl bromides, as both enantiomers have an equal chance of being attacked from either side. On the other hand, (R)-2-butanol, being the enantiomer of (S)-2-butanol, will also undergo the same reaction and produce the same racemic mixture of alkyl bromides.
In the case of (R)-1-phenyl ethanol and (S)-1-phenyl ethanol, they are secondary alcohols and can undergo either SN1 or SN2 reactions depending on the reaction conditions. However, the reaction mechanism will lead to the formation of a mixture of diastereomers, rather than a racemic mixture of enantiomers.
To learn more about alkyl bromides
https://brainly.com/question/29031148
#SPJ4
Complete question:
Which of the following optically active alcohols, when treated with HBr, results in a racemic mixture of alkyl bromides?
a) (R)-2-butanol
b) (S)-2-butanol
c) (R)-1-phenyl ethanol
d) (S)-1-phenyl ethanol
Which transition metal can form both a high and low spin complex? Zn2+, Cu2+, Mn3+, Ti2+
Answer: Manganese
Explanation:
With titanium, it only has two d electrons, so it can't form different high and low spin complexes. It doesn't matter because it will never fill the higher-energy orbitals. The total spin state turns out to be +1 (two unpaired d electrons, no matter what). Therefore, manganese will form both a high and low spin complex.
Which statement below correctly describes their relative atomic radii and first ionization energy when comparing Se and Br? The atomic radius for Se is larger than Br, and the first ionization energy for Se is greater than Br. The atomic radius for Br is larger than Se, and the first ionization energy for Bris greater than Se. The atomic radius for Se is larger than Br, and the first ionization energy for Br is greater than Se. The atomic radius for Br is larger than Se, and the first ionization energy for Se is greater than Br.
At has a higher initial ionisation energy than Br, while Br has a bigger atomic radius. Se has a bigger atomic radius than Br, and Br has a higher initial ionisation energy than Se.
How do atomic radii and ionisation energy relate to one another (i.e., what happens to ionisation energy as atomic radii grow)?The most loosely bound electron is further from the nucleus and thus easier to remove in bigger atoms. Hence, the ionisation energy should decrease as size (atomic radius) increases.
Why does ionisation energy rise across a period while decreasing down a group?This is because the outer electrons aren't bound as strongly because they are farther from the nucleus.
To know more about ionisation energy visit:-
brainly.com/question/27356170
#SPJ1
A student sets up a titration with a * 1 point buret filled with 0.5 M NaOH. In the flask below they place the phenolphthalein indicator and 6.2 mL of the unknown acid. The solution in the beaker turns pink after exactly 24.8 mL of NaOH have been added. Find the exact concentration of the unknown acid.
which of the following alkenes is most stabilized through hyperconjugation? select answer from the options below
The alkene that is most stabilized through hyperconjugation is 2-methylpropene. The correct option is (C).
Hyperconjugation is a type of resonance that involves the overlapping of an unshared electron pair on an atom, like carbon, with an adjacent sigma bond. In this case, the unshared electron pair on the methyl group of 2-methylpropene provides stabilization to the adjacent sigma bond, making it the most stabilized alkene through hyperconjugation.
The most stabilized alkene through hyperconjugation can be determined by analyzing the degree of substitution. The greater the number of alkyl groups attached to the carbon atoms of the double bond, the greater the degree of substitution and the greater the stability due to hyperconjugation. Hence, the answer to this question would be option C (2-methylpropene.), as it has the greatest degree of substitution and is thus the most stable through hyperconjugation.
Option A (1-butene) has only one methyl group attached to one carbon of the double bond, making it less stable than option C. Option B (2-butene) has two methyl groups attached to the same carbon atom of the double bond, resulting in a similar degree of substitution to option A. Option D (2-methyl-1-pentene) has a lesser degree of substitution than option C because the methyl group is attached to only one carbon atom of the double bond, while in option C, the methyl group is attached to a tertiary carbon atom.
Hence, option C , 2-methylpropene. is the most stabilized alkene through hyperconjugation because of its greater degree of substitution.
For more such questions on Hyperconjugation , Visit:
https://brainly.com/question/28031100
#SPJ11
The complete question is:
which of the following alkenes is most stabilized through hyperconjugation? select answer from the options below
A 1-butene
B 2-butene
C 2-methylpropene
D 2-methyl-1-pentene
How many atoms of lithium are in 18.7 g?
The atoms of lithium that are in 18.7 g is 16 × 10²³ atoms . This is taken out by mole concept .
What is mole concept ?The mole is a unit of measurement similar to the pair, dozen, gross, and so on. It provides a precise count of the atoms or molecules in a bulk sample of matter. A mole is the amount of substance that contains the same number of discrete entities (atoms, molecules, ions, etc.)
if 7 grams of lithium contain 6 × 10²³ atoms
then 18.7 will contain 16 × 10²³ atoms
to know more about mole concept , visit ;
brainly.com/question/31123980
#SPJ1
Given that 4 NH3 + 5 O2 → 4 NO + 6 H2O, if 3.00 mol NH3 were made to react with excess of oxygen gas, the amount of H2O formed would be
For Mn3+, write an equation that shows how the cation acts as an acid. express your answer as a chemical equation including phases.
Mn3+, an ion of manganese(III), can function as an acid by giving a proton (H+) to a base. Here's an illustration: Mn3+ (aq) + 3OH- (aq) Mn(OH)3 (s)
What colour are Mn2+ and MnO4?There is no need to add an indicator because MnO4's vivid purple colour serves as one enough. In the conical flask, there is Fe2+. The Fe2+ solution is added, and the Fe2+ lowers the MnO4- to Mn2+. As Mn2+ is a colourless solution, the purple colour disappears.
What is the ion Mn2name? +'sThe divalent metal cation manganese(2+) contains manganese as the metal. It plays the part of a cofactor. It consists of a monoatomic dication, a manganese cation, and a divalent metal cation.
To know more about cation visit:-
https://brainly.com/question/28710898
#SPJ1
identify which of the following atoms would have the lowest first ionization energy. a) ca b) c c) ge d) p e) cl
The atom with the lowest first ionization energy is C (carbon). The order from highest to lowest is: e) Cl (chlorine) > d) P (phosphorus) > c) Ge (germanium) > b) C (carbon) > a) Ca (calcium).
The atom that would have the lowest first ionization energy is Ca (Calcium). The amount of energy that is required to remove the most loosely held electron from an isolated neutral gaseous atom to form a cation is called the first ionization energy. It is a measure of the stability of an atom. The ionization energy of an element is determined by the amount of energy required to remove an electron from its ground state. The ionization energy is a physical property of an element that varies across the periodic table. The element that has the lowest ionization energy is the most reactive and will most likely form cations.
Identify which of the following atoms would have the lowest first ionization energy. The given atoms are Ca, C, Ge, P, and Cl. Out of these atoms, Ca would have the lowest first ionization energy. The electronic configuration of Ca is 2, 8, 8, 2. Calcium belongs to group 2 and period 4 of the periodic table. It has 20 protons, 20 electrons, and 2 valence electrons. Because of its 2 valence electrons, it has a low ionization energy. The electronic configuration of Ca is most stable because of the presence of the 8 valence electrons in the outermost shell.
The electronic configurations of the other given atoms are:
C: 2, 4Ge: 2, 8, 18, 4P: 2, 8, 5Cl: 2, 8, 7
All of these elements have electrons that are either in the process of filling the valence shell or have already filled it. They have higher ionization energies because of this. Therefore, Ca would have the lowest first ionization energy.
For more such questions on ionization energy , Visit:
https://brainly.com/question/20658080
#SPJ11
The enthalpy of vaporization for dimethyl ether is 27.5 kJ/mol. Dimethyl ether has a vapor pressure of 760 torr at 34.6 oC. Using the Clausius-Clapeyron equation, what is the vapor pressure for methanol at 4.2 oC? Give your answer in torr, to the first decimal point.
The vapor pressure of methanol at 4.2 oC is approximately 1.6 torr.
What is the vapor pressure of methanol?The Clausius-Clapeyron equation relates the vapor pressure of a substance at two different temperatures and its enthalpy of vaporization. The equation is:
ln(P2/P1) = (-ΔHvap/R)(1/T2 - 1/T1)
where;
P1 and T1 are the vapor pressure and temperature at the first state, P2 and T2 are the vapor pressure and temperature at the second state, ΔHvap is the enthalpy of vaporization, R is the gas constant, and ln is the natural logarithm.We are given the enthalpy of vaporization for dimethyl ether, which is 27.5 kJ/mol. We are also given the vapor pressure of dimethyl ether at 34.6 ⁰C, which is 760 torr.
We want to find the vapor pressure of methanol at 4.2 ⁰C.
Let's choose the vapor pressure of dimethyl ether at 34.6 ⁰C as the first state, and the vapor pressure of methanol at 4.2 ⁰C as the second state. We can convert the temperatures to kelvin by adding 273.15:
T1 = 34.6 + 273.15 = 307.75 K
T2 = 4.2 + 273.15 = 277.35 K
We can plug in the values into the Clausius-Clapeyron equation:
ln(P2/760) = (-27.5×10^3 J/mol)/(8.314 J/(mol·K)) × (1/277.35 K - 1/307.75 K)
Simplifying:
ln(P2/760) = -5.721
Taking the exponential of both sides:
P2/760 = e^-5.721
Multiplying both sides by 760:
P2 = 1.65 torr (to the nearest tenth)
Learn more about vapor pressure here: https://brainly.com/question/4463307
#SPJ1
The titration of 45.0 ml of an unknown triprotic acid required 32.71 ml of 0.37 M KOH to
reach the endpoint. What is the molarity of the unknown acid?
The molarity of the unknown triprotic acid is 0.269M.
How to calculate molarity?Molarity is the concentration of a substance in solution, expressed as the number moles of solute per litre of solution.
The molarity of the unknown acid can be calculated using the following formula:
CaVa = CbVb
Where;
Ca and Va = acid concentration and volume respectivelyCb and Vb = base concentration and volume respectivelyAccording to this question, the titration of 45.0 ml of an unknown triprotic acid required 32.71 ml of 0.37 M KOH to reach the endpoint.
45 × Ca = 32.71 × 0.37
45Ca = 12.1027
Ca = 0.269M
Learn more about molarity at: https://brainly.com/question/8732513
#SPJ1
2. Assume
60.0 mL
of a
2.5M
potassium chromate solution is mixed with
40.0 mL
of a
3.2M
solution of iron (III) chloride. a) Will a reaction occur and if so, what reaction will occur? b) How much precipitate will be produced in grams? c) What is the concentration of each spectator ion in the final solution? What is the concentration of left-over ions in the solution? (Calculate the final concentration of each ion).
Previous qu
The displacement reaction will occur. The concentration of each spectator ion in the final solution is 3/2 moles of Fe2(CrO4)3 will be formed and Concentration of CrO4^2- will be 0.033 M
Step 1:
The balanced chemical equation for the reaction is given below:
K2CrO4 + FeCl3 -> Fe2(CrO4)3 + 2KCl
Hence, the reaction occurs between potassium chromate and iron (III) chloride.
Step 2:
We need to find out how much precipitate will be produced in grams.
Let's calculate the moles of reactants and then use mole ratio to find out the limiting reagent:
[tex]\[\text{Moles of potassium chromate} = \text{Molarity} \times \text{Volume} \div 1000\][Molarity of K2CrO4 = 2.5 M; Volume of K2CrO4 = 60.0 mL][/tex]
Moles of K2CrO4 = (2.5 x 60.0) / 1000 = 0.150 mol
[tex]\[\text{Moles of iron (III) chloride} = \text{Molarity} \times \text{Volume} \div 1000\][Molarity of FeCl3 = 3.2 M[/tex] = 3.2 M;
Volume of FeCl3 = 40.0 mL]Moles of FeCl3 = (3.2 x 40.0) / 1000 = 0.128 mol
As we see, K2CrO4 is the limiting reagent. So, FeCl3 is in excess.
Therefore, amount of Fe2(CrO4)3 precipitated is given by moles of K2CrO4 and mole ratio:
[tex]\[\text{Moles of Fe2(CrO4)3} = \text{Moles of K2CrO4} = 0.150 mol\][/tex]
Now, we will find the molecular weight of Fe2(CrO4)3 as 479.87 g/mol.
[tex]\[\text{Mass of Fe2(CrO4)3} = \text{Moles of Fe2(CrO4)3} \times \text{Molecular weight}\][/tex]
[tex]\[\text{Mass of Fe2(CrO4)3} = 0.150 \times 479.87 = 71.98\][/tex]
Therefore, the amount of precipitate produced is 71.98 g.c
We need to find out the concentration of each spectator ion in the final solution.
Firstly, we can write down the ionic equation for the reaction:
[tex]2 K+ + CrO4^2- + 3 Fe^3+ + 3 Cl^- - > 2 K+ + 3 Cl^- + Fe2(CrO4)3[/tex]
Now, we will check which ions remain in the final solution. We see that potassium and chloride ions are spectator ions. Hence, we don't need to calculate their concentration. The concentration of remaining ions can be calculated as follows:Fe3+ ions: In the given reaction, 3 moles of FeCl3 reacts with 2 moles of K2CrO4.
Hence, 3/2 moles of Fe2(CrO4)3 will be formed.
Therefore,
= [tex]\frac{3/2 \times 3.2 \times 40.0 \div 1000}{60.0 + 40.0}[/tex]
= 0.034 M\]CrO42- ions:
In the given reaction, 2 moles of K2CrO4 reacts with 3 moles of FeCl3.
Hence, 2/3 moles of Fe2(CrO4)3 will be formed.
Therefore,
Concentration{ of CrO4^2-}
= [tex]\frac{2/3 \times 2.5 \times 60.0 \div 1000}{60.0 + 40.0}[/tex]
= 0.033 M\]
For more such questions on displacement reaction , Visit:
https://brainly.com/question/20690229
#SPJ11
what happens when zinc chloride reacts with potassium hydroxide and what formed?
Answer:
when the solution of potassium hydroxide and zinc chloride are mixed,the double-displacement reaction occur ,resulting in precipitation and the reaction forms potassium chloride and zinc hydroxide .
A 0.036 M aqueous nitrous acid (HNO2) solution has an osmotic pressure of 0.93 atm at 25°C. Calculate the percent ionization of the acid.
The percent ionization of the nitrous acid in the 0.036 M aqueous solution is 2.1%.
How to calculate the percent ionization of the acid ?
The osmotic pressure (π) of a solution can be related to the molar concentration (M) of the solute and the temperature (T) of the solution by the following equation:
π = MRT
Where R is the gas constant.
We can use this equation to calculate the molar concentration of the nitrous acid solution:
M = π / RT
M = (0.93 atm) / (0.0821 L·atm/(mol·K) x 298 K)
M = 0.036 M
This is the molar concentration of the undissociated nitrous acid in the solution. To calculate the percent ionization of the acid, we need to know the concentration of the H+ and NO2- ions in the solution.
The balanced chemical equation for the dissociation of nitrous acid is:
HNO2(aq) ⇌ H+(aq) + NO2-(aq)
Let x be the extent of ionization of the nitrous acid. Then the concentration of H+ and NO2- ions can be expressed in terms of x as follows:
[H+] = x M
[NO2-] = x M
The concentration of the undissociated nitrous acid is (1-x)M.
The expression for the equilibrium constant (Ka) of the reaction can be written as:
Ka = [H+] [NO2-] / [HNO2]
Substituting the concentrations in terms of x, we get:
Ka = x^2M / (1-x)M
Simplifying the above equation, we get:
Ka = x^2 / (1-x)
The percent ionization of the acid is the fraction of the original HNO2 molecules that dissociate into H+ and NO2- ions. It can be calculated as follows:
% ionization = (concentration of H+ ions) / (initial concentration of HNO2) x 100
% ionization = (x M) / (M) x 100
% ionization = x x 100
Substituting the value of x from the above equation for Ka, we get:
Ka = x^2 / (1-x)
x = sqrt(Ka / (1+Ka))
We can calculate the value of Ka using the standard reference value of the acid dissociation constant (Ka) for nitrous acid at 25°C, which is 4.5 x 10^-4.
x = sqrt(4.5 x 10^-4 / (1+4.5 x 10^-4))
x = 0.021
% ionization = 0.021 x 100
% ionization = 2.1%
Therefore, the percent ionization of the nitrous acid in the 0.036 M aqueous solution is 2.1%.
Learn more about osmotic pressure here : brainly.com/question/25413362
#SPJ1
AsH3, HBr, KH, H2Se arrange in increasing order of acid strength
Answer:
Transcribed Image Text: Rank the following substances in order of increasing acid strength. (1 as least and 4 as most in acid strength) ✓ H₂Se ✓ HBr HI ✓ AsH3 Expert Solution
Explanation:
HOPE IT HELPS!!
structural change from a myoglobin tertiary structure to the inclusion of quaternary structure for hemoglobin
The quaternary structure of hemoglobin is responsible for the increased oxygen-carrying capacity and stability of the molecule. This structure allows hemoglobin to better transport oxygen throughout the body and is essential to life.
The structural change from myoglobin to hemoglobin includes an additional quaternary structure, which is the arrangement of two or more myoglobin subunits into a single, functional entity. This structural change allows for the cooperative binding of oxygen, meaning that the hemoglobin molecule can carry more oxygen than a single myoglobin molecule can. This is due to the increased surface area of the hemoglobin molecule, which provides more oxygen-binding sites. Additionally, the quaternary structure of hemoglobin increases the stability of the molecule, meaning it can better resist changes in pH or temperature. This is important because it allows hemoglobin to function in the wide range of temperatures and environments that are found within the human body.
To learn more about Hemoglobin :
https://brainly.com/question/11102357
#SPJ11
It is advantageous for a predator to prey exclusively on a single prey species
Answer: It is not necessarily advantageous for a predator to prey exclusively on a single prey species, as this can limit their options and make them vulnerable if the population of that prey species declines or becomes extinct. Predators that are more flexible and able to switch between different prey species may be better equipped to survive and thrive in changing environments.
However, there are some advantages to specializing in a single prey species. For example, a predator that is well adapted to hunting a particular prey species may be more efficient and successful at capturing and consuming that prey, which could provide a reliable source of energy. Additionally, if the predator and prey have co-evolved, the predator may have adaptations that specifically allow it to exploit the weaknesses or vulnerabilities of its prey, giving it an advantage over predators that are less specialized.
how many elements are found in the formula 3He2O4PH
There are four (4) elements in the chemical formula given above.
What is a chemical formula?Chemical formula in chemistry is a notation indicating the number of atoms of each element present in a compound.
The chemical formula of a substance shows the types and number of elements present in such substance.
According to this question, the chemical formula of a substance is given. The elements present in the compound based on their symbols are as follows:
Helium (He)Oxygen (O)Phosphorus (P)Hydrogen (H)Therefore, there are four elements in the substance.
Learn more about chemical formula at: https://brainly.com/question/29031056
#SPJ1
Which equation is a correctly written thermochemical equation?
OC3H8 (g) +502 (g) → 3CO2 (g) + 4H₂O (1), AH= -2,220 kJ/mol
OFe (s) + O2 (g) → Fe₂O3 (s), AH= -3,926 kJ
ONH₂Cl → NH₂ + + Cl
O2C8H18 + 250216CO2 + 18H₂O, AH=-5,471 kJ/mol
Answer:
The correctly written thermochemical equation is:
C3H8 (g) + 5O2 (g) → 3CO2 (g) + 4H2O (l), ΔH = -2,220 kJ/mol
This equation represents the combustion of propane (C3H8) in the presence of oxygen (O2) to produce carbon dioxide (CO2) and water (H2O), with a heat release of -2,220 kJ/mol. The state symbols (g) for gases and (l) for liquids indicate the physical state of each substance at standard conditions.
Explanation:
ABOVE
What is the bond angle of carbonothioyl dibromide
Also what is the molecular shape
Answer:
Carbonothioyl dibromide, also known as CBr2S, has a bond angle of approximately 109.5 degrees, which is the typical tetrahedral bond angle for molecules with sp3 hybridization.
The molecular shape of CBr2S is also tetrahedral, with the two bromine atoms and the sulfur atom arranged at the corners of a tetrahedron, and the carbon atom at the center.
Part 1. A lightly inflated balloon is placed in a freezer. Explain the change to the size of the balloon based on the kinetic molecular theory.
Part 2. What would most likely happen to the balloon if it was instead kept outside in the sun for some time? Explain your answer based on the kinetic molecular theory.
In both cases, assume the balloon is tied tight enough so that air does not escape.
Part 1: When a lightly inflated balloon is placed in a freezer, the temperature of the air molecules inside the balloon decreases. According to the kinetic molecular theory, the volume of a gas is directly proportional to its temperature. As the temperature of the air molecules inside the balloon decreases, the average kinetic energy of the air molecules also decreases, causing the gas to contract. This contraction leads to a decrease in the volume of the gas inside the balloon, which causes the balloon to shrink in size.
Part 2: If the balloon is instead kept outside in the sun for some time, the temperature of the air molecules inside the balloon will increase. According to the kinetic molecular theory, an increase in temperature leads to an increase in the average kinetic energy of the gas molecules, causing them to move faster and collide more frequently. This increased collision frequency leads to an increase in pressure, which causes the balloon to expand in size. Therefore, the balloon will most likely get bigger when it is exposed to the heat of the sun.
Answer:
simple answer
Explanation:
part 1: if the balloon's temperature decreases so does the air molecules within it. The gas contracts because it's in a seal place, causing the balloon to shrink.
part 2: the balloon is exposed to heat, so the temperature is obviously going to increase as well as the air molecules. Gas molecules are moving rapidly causing the balloon to expand.
Chemistry Help Please! It's worth a lot of points
1.Write the equilibrium expression for the following reactions
a. H2SO4(aq) + H2O(L) ⇆ HSO4-(aq) + H3O+(aq)
b. 4NH3(g) + 5O2(g) ⇆ 4NO(g) + 6H2O(g)
c. NH4Cl(s) ⇆ NH3(g) + HCl(g)
d. N2O4(g) ⇆ 2NO2(g)
2. The following reaction has a K value of 0.050. What does that mean about the concentrations of the reactants as compared to the products? Be specific in your answer.
N2(g) + 3H2(g) ⇆ 2NH3(g)
3. The following reaction has a K value of 6.8 x 103. What does that mean about the concentrations of the reactants as compared to the products? Be specific in your answer.
2SO3(g) ⇆ 2SO2(g) + O2(g)
4. When dissolving substances in water, the degree of solubility of a substance is often represented as the solubility product constant (Ksp). The solubility product constant is the same thing as the equilibrium constant for the dissolving reaction. Two substances that dissociate in water are shown below alone with the Ksp.
NaCl(s) ⇆ Na+(aq) + Cl-(aq) Ksp = 36
BaSO4(s) ⇆ Ba2+(aq) + SO42-(aq) Ksp = 1.1 x 10-16
5. Identify and label the Brønsted-Lowry acid, its conjugate base, the Brønsted-Lowry base, and its conjugate acid in each of the following equations:
a. HNO3 + H2O ⟶ H3O+ + NO3−
b. CN− + H2O ⟶ HCN + OH−
c. H2SO4 + Cl− ⟶ HCl + HSO4−
d. HSO4− + OH− ⟶ SO42− + H2O
e. O2− + H2O ⟶2OH−
6. What is the conjugate acid of each of the following? What is the conjugate base of each of the following?
a. OH-
b. H2O
c. HCO3-
d. NH3
e. HSO4-
7. The following acids are shown with their equilibrium constants (also known as the acid dissociation constant). Rank these acids from strongest to weakest. Explain your ranking.
HCN(aq) + H2O(L) ⇆ H3O+(aq) + CN-(aq) K = 6.2 x 10-10
HC2H3O2(aq) + H2O(L) ⇆ H3O+(aq) + C2H3O-(aq) K = 1.75 x 10-5
H2CO3(aq) + H2O(L) ⇆ H3O+(aq) + HCO3-(aq) K = 4.5 x 10-7
HIO4(aq) + H2O(L) ⇆ H3O+(aq) + IO4-(aq) K = 2.3 x 10-2
8. Calculate the pH and the pOH of each of the following solutions.
a. 0.200 M HCl
b. 0.0143 M NaOH
c. 3.0 M HNO3
d. 0.0031 M Ca(OH)2
9. Wine has a pH of 3.6. What are the hydronium and hydroxide ion concentrations?
10. The hydroxide ion concentration in household ammonia is 3.2 x 10-3 M. What is the concentration of hydronium ions?
Answer:
1. Equilibrium expressions:
a. K = [HSO4-][H3O+]/[H2SO4][H2O]
b. K = [NO]^4[H2O]^6/[NH3]^4[O2]^5
c. K = [NH3][HCl]/[NH4Cl]
d. K = [NO2]^2/[N2O4]
2. Since K = 0.050, the concentrations of the reactants (N2 and H2) are larger than the concentrations of the products (NH3).
3. Since K = 6.8 x 10^3, the concentrations of the products (SO2 and O2) are larger than the concentrations of the reactant (SO3).
4. The Ksp expression for each of the reactions is:
a. Ksp = [Na+][Cl-]
b. Ksp = [Ba2+][SO42-]
5. Brønsted-Lowry acids and bases:
a. Acid: HNO3; Conjugate base: NO3-; Base: H2O; Conjugate acid: H3O+
b. Acid: HCN; Conjugate base: CN-; Base: H2O; Conjugate acid: HCN
c. Acid: H2SO4; Conjugate base: HSO4-; Base: Cl-; Conjugate acid: HCl
d. Acid: NH3; Conjugate base: NH2-; Base: H2O; Conjugate acid: NH4+
e. Acid: H2O; Conjugate base: OH-; Base: O2-; Conjugate acid: OH-
6. Conjugate acids and bases:
a. Acid: H2O; Conjugate base: OH-
b. Acid: H3O+; Conjugate base: H2O
c. Acid: H2CO3; Conjugate base: HCO3-
d. Acid: NH4+; Conjugate base: NH3
e. Acid: HSO4-; Conjugate base: SO42-
7. The strongest acid is HIO4 (highest K value), followed by HCN, HC2H3O2, and H2CO3 (lowest K value). The K values represent the degree to which the acids dissociate in solution. HIO4 is a strong acid, meaning it dissociates almost completely in solution, while H2CO3 is a weak acid, meaning it only dissociates partially.
8. pH and pOH calculations:
a. pH = -log[H3O+] = -log(0.200) = 0.699; pOH = -log[OH-] = -log(1.0 x 10^-14/0.200) = 12.301
b. pOH = -log[OH-] = -log(0.0143) = 1.844; pH = 14.000 - pOH = 12.156
c. pH = -log[H3O+] = -log(3.0) = 0.522; pOH = 13.478
d. pOH = -log[OH-] = -log(0.0062) = 2.206; pH = 14.000 - pOH = 11.794
9. Hydronium and hydroxide ion concentrations:
pH = 3.6; hydronium ion concentration = 10^-pH = 3.98 x 10^-4 M; hydro
(Please could you kindly mark my answer as brainliest you could also follow me so that you could easily reach out to me for any other questions)
A 106 mL solution of a dilute acid is added to 157 mL of a base solution in a coffee-cup calorimeter. The temperature of the solution increases from 22.94 oC to 27.29 oC. Assuming the mixture has the same specific heat (4.184J/goC) and density (1.00 g/cm3) as water, calculate the heat (in J) transferred to the surroundings, qsurr.
Answer:
4897 J
Explanation:
The heat transferred to the surroundings, q_surr, can be calculated using the equation:
q_surr = -q_rxn = -CmΔT
where C is the specific heat capacity of the mixture (assumed to be the same as water, 4.184 J/g°C), m is the mass of the mixture (which we can calculate using the density, assuming that the volumes are additive), and ΔT is the change in temperature (in Celsius).
First, let's calculate the mass of the mixture:
density of water = 1.00 g/cm^3
volume of mixture = volume of acid + volume of base = 106 mL + 157 mL = 263 mL = 0.263 L
mass of mixture = density of water x volume of mixture = 1.00 g/cm^3 x 0.263 L = 263 g
Next, let's calculate the change in temperature:
ΔT = final temperature - initial temperature = 27.29°C - 22.94°C = 4.35°C
Now we can calculate the heat transferred to the surroundings:
q_surr = -CmΔT
q_surr = -(4.184 J/g°C) x (263 g) x (4.35°C)
q_surr = -4897 J
Note that the negative sign indicates that heat is lost by the system to the surroundings. Therefore, the heat transferred to the surroundings, q_surr, is 4897 J.
What is the amount of pi?
However, it is commonly approximated as 3.14159.
What is an irrational number ?An irrational number is a number that cannot be expressed as a simple fraction or ratio of two integers. It is a non-repeating, non-terminating decimal. Examples of irrational numbers include pi (π), the square root of 2 (√2), and the golden ratio (∅).
What is a termination ?In mathematics, a terminating decimal is a decimal number that has a finite number of digits after the decimal point, i.e., the decimal representation ends in a finite number of zeroes. For example, 0.75, 2.0, and 0.0625 are terminating decimals.
To know more about irrational visit :
https://brainly.com/question/15837135
#SPJ1
Write the electronic configuration and draw the orbital diagram for the element: lead (Z=82) State if it is diamagnetic/paramagnetic. Please decide the diamagnetic/paramagnetic property based on the orbital diagram only! (It is okay to use the noble gas in square brackets here)
Answer:
See below.
Explanation:
The atomic number of lead (Pb) is 82, which means it has 82 electrons. The electronic configuration of lead is
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p²
The orbital diagram for the valence electrons of lead (Pb) is
↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓
s s p p p p d d
2 1 6 2 6 2 10 10
|||||||||
1 2 3 4 5 6 7 8
The notation ↑↓ represents a pair of electrons with opposite spins.
To determine if lead (Pb) is diamagnetic or paramagnetic, we need to look at whether there are any unpaired electrons. Based on the orbital diagram, we can see that all the electrons in the valence shell are paired, meaning that lead (Pb) is diamagnetic.
one chemical formula of this element with oxygen is eo2, write the electronic configuration for the ion formed from e in this compound.
The element in question here is E, and its chemical formula with oxygen is EO2. the electronic configuration of the ion formed from E in EO2 is 1s²2s²2p⁶.
Electronic configuration refers to the distribution of electrons among different energy levels and subshells of an atom. When E forms a compound with oxygen, it loses two electrons to form a cation with a 2+ charge. This cation is written as E2+ and has an electronic configuration of 1s²2s²2p⁶. The electronic configuration of E before it forms a compound with oxygen can be found by considering its position in the periodic table. E is in the third row and fourth column of the periodic table, which means that it has three energy levels and four valence electrons.
Therefore, its electronic configuration is 1s²2s²2p⁶3s²3p². When E forms a compound with oxygen, it loses two valence electrons from its outermost energy level, which is the third energy level in this case. This results in the formation of E2+ ions with an electronic configuration of 1s²2s²2p⁶. Thus, the electronic configuration of the ion formed from E in EO2 is 1s²2s²2p⁶.
Know more about electronic configuration here:
https://brainly.com/question/29564763
#SPJ11
Four ATP molecules are made in the second step in glycolysis. However, the net production of ATP is two because Multiple Choice O two molecules of ATP are used to move glucose into the chloroplast o two molecules of ATP are needed to "activate glucose O ATP production cannot exceed NADH production O glycolysis is the final step of aerobic respiration o U glycolysis may occur without oxygen being present
The correct answer is "two molecules of ATP are needed to 'activate' glucose".
In the first step of glycolysis, glucose is converted into glucose-6-phosphate, which requires the input of ATP. This reaction is catalyzed by the enzyme hexokinase. Therefore, two molecules of ATP are used in the early steps of glycolysis to activate glucose and convert it into glucose-6-phosphate. In the later steps of glycolysis, four molecules of ATP are produced by substrate-level phosphorylation, but since two molecules of ATP were used in the beginning, the net production of ATP is only two molecules per glucose molecule.
It is also important to note that glycolysis is the first step of both aerobic and anaerobic respiration and can occur without oxygen being present. However, the subsequent steps of cellular respiration, such as the Krebs cycle and electron transport chain, require oxygen in aerobic respiration to produce more ATP.
What is an ATP?
ATP stands for Adenosine Triphosphate, which is a molecule that carries energy within cells. It is often referred to as the "energy currency" of the cell because it powers many cellular processes by releasing its stored energy when it is hydrolyzed to ADP (Adenosine Diphosphate) and inorganic phosphate.
To know more about ATP, visit:
https://brainly.com/question/174043
#SPJ1
There are 7.68 × 1025 atoms of phosphorous in how many moles of diphosphorous pentoxide?
Answer:
7.68 x 1025 atoms of phosphorous correspond to 1.06 mole of diphosphorous pentoxide. This can also be written as 1.06 mol of P2O5.
Predict the principal organic product of the following reaction. Specify stereochemistry where appropriate.
The major organic product of an SN2 substitution reaction is an alkene, which may be either in retention or inversion of configuration relative to the original substrate.
The reaction you are asking about is an SN2 substitution reaction, in which a nucleophile (Nu) displaces a leaving group (LG) from a molecule with an alkyl halide substrate. The major organic product of this reaction will be an alkene, which has the same carbon chain as the alkyl halide substrate. Depending on the relative configuration of the substrate, the alkene product may be the same as the original substrate (retention) or have its configuration inverted (inversion). If stereochemistry is relevant to the question, then it should be specified in the answer.
To learn more about SN2 substitution :
https://brainly.com/question/29849583
#SPJ11
