A small coffee cup calorimeter contains 28.0 g of H2O at 19.73 oC. A 2.05 g sample of a metal alloy is heated to 98.88 oC and then placed in the water. The contents of the calorimeter come to a temperature of 21.23 oC. What is the specific heat of lead
Answer:
1.104 J/g°C
Explanation:
Using Q = m × c × ∆T
Where;
m = mass of substance (g)
c = specific hear capacity (J/g°C)
∆T = change in temperature (°C)
For a colorimeter,
Q(water) = - Q(metal)
m. c. ∆T (water) = - m. c. ∆T (metal)
According to the information provided;
For water:
m = 28.0g
c = 4.184 J/g°C
∆T = (21.23 - 19.73°C)
For the metal:
m = 2.05g
c = ?
∆T = (21.23 - 98.88°C)
m. c. ∆T (water) = - m. c. ∆T (metal)
[28 × 4.184 × (21.23 - 19.73°C)] = -[2.05 × c × (21.23 - 98.88°C)]
[117.152 × 1.5] = -[2.05 × c × (-77.65)]
175.728 = -[-159.1825c]
175.728 = 159.1825c
c = 175.728 ÷ 159.1825
c = 1.104
c = 1.104 J/g°C
5.96 g of ammonia reacts completely according to the following reaction:
2 NH, (g) + Co, (g) → CN,OH, (s) + H20 (1)
(a) What is the theoretical yield of urea (CN,OH,) for this reaction?
(b) If 13.74 g of urea are produced, what is the percent yield for this equation?
please show work, will give brainliest
Explanation:
this explanation may help u to understand:)
Which compound is insoluble in water?
Answer:
The answer is C... I am almost positive.
how old was the oldest animal fossil
help thx
Answer:
the Rhyniognatha hirsti
Explanation:
at age 400 million years old
Helppp
What do you need to know in order to find the mass of 3.00 moles of carbon?
Answer:
36g
Explanation:
you need to know the equation mass=moles*mr (in this case mr of carbon which is 12)
so 3*12=36g
hope this helps :)
Phosphine, PH3, a reactive and poisonous compound, reacts with oxygen as follows: 4PH3(g) 8O2(g) - P4O10(s) 6H2O(g) If you need to make 6.5 moles of P4O10, how many moles of PH3 is required for the reaction
Answer: 26 moles of [tex]PH_3[/tex] are required for the reaction.
Explanation:
We are given:
Moles of [tex]P_4O_{10}[/tex] = 6.5 moles
The given chemical reaction follows:
[tex]4PH_3(g)+8O_2(g)\rightarrow P_4O_{10}(s)+6H_2O(g)[/tex]
By the stoichiometry of the reaction:
If 1 mole of [tex]P_4O_{10}[/tex] is produced by 4 moles of [tex]PH_3[/tex]
So, 6.5 moles of [tex]P_4O_{10}[/tex] will be produced by = [tex]\frac{4}{1}\times 6.5=26mol[/tex] of [tex]PH_3[/tex]
Hence, 26 moles of [tex]PH_3[/tex] are required for the reaction.
Please help me, it’s my last try
Answer:
Group 1A: alkali metals, or lithium family.
Group 2A: alkaline earth metals, or beryllium family.
Group 7A: the manganese family.
Group 8A: the iron family.
Explanation:
Answer:
1A: Alkali Metals
2A: Alkaline Earth Metals
7A: Halogens
8A: Noble Gases
20. What is an irreversible change?
Answer:
A change is called irreversible if it cannot be changed back again. For example you cannot change a cake back into its ingredients again. Irreversible changes are permanent.
Explanation:
Hope this helps!! :))
which of the following illustrates a reversible change a cooking corn be rusting c frying egg and the boiling water
What are the laws and calculations governing gas behavior?
Answer:
Laws governing gas behavior.
Explanation:
Boyle's law:
It relates the pressure and volume of an ideal gas at a constant temperature.
According to this law:
"The volume of a fixed amount of gas at constant temperature is inversely proportional to its pressure".
[tex]P \alpha V[/tex].
Charle's law:
It relates the volume and absolute temperature of an ideal gas at a constant pressure.
According to this law:
"The volume of a fixed amount of gas at constant pressure is directly proportional to its absolute temperature".
[tex]V \alpha T[/tex].
Avogadro's law:
According to this law:
equal volumes of all gases under the same conditions of temperature and pressure contain, an equal number of moles.
[tex]V \alpha n[/tex].
Ideal gas equation:
By combining all the above-stated gas laws, this equation is formed as shown below:
[tex]V \alpha \frac{nT}{P} \\=> V= R. nT/ P\\=>PV=nRT[/tex]
R is called universal gas constant.
It has a value of 0.0821L.atm.mol-1.K-1.
Answer:
Boyle's law, Charle's law, Guy Lussac's law and Avogadro's law
Explanation:
All the gases behaves similarly when the environment conditions are normal. But when the physical condition changes like when the pressure, volume or temperature changes, the gas behaves differently and shows a deviation.
The number of gas laws are :
Boyle's Law
Boyle's law states that when the temperature remaining constant, the pressure of the gas varies inversely to the volume of the gas.
i.e. [tex]P \propto \frac{1}{V}[/tex]
Charle' law
Charle's law states that when pressure is constant, the temperature of a gas is directly proportional to the volume.
i.e. , [tex]$T \propto V$[/tex]
Gay Lussac's law
Gay - Lussa law states the volume and the mass of the pressure of the gas is directly proportional to the temperature of the gas.
i.e. P.T = constant
Avogadro's law
It states that under the conditions of same pressure as well as temperatures, the gases having equal volumes will have same numbers of molecules.
i.e. [tex]\frac{V_1}{n_1}=\frac{V_2}{n_2}[/tex] = constant
In the reaction below, what is the limiting reactant when 1.24 moles NH3 of reacts with 1.79 moles of NO?
4NH_3 + 6NO (right arrow) 5N_2 + 6H_2O
1. NO
2. H_2O
3. NH_3
4. N_2
Answer:
Option 1. NO
Explanation:
The balanced equation for the reaction is given below below:
4NH₃ + 6NO —> 5N₂ + 6H₂O
From the balanced equation above,
4 moles of NH₃ reacted with 6 moles of NO.
Finally, we shall determine the limiting reactant. This can be obtained as follow:
From the balanced equation above,
4 moles of NH₃ reacted with 6 moles of NO.
Therefore, 1.24 moles of NH₃ will react with = (1.24 × 6)/4 = 1.86 moles of NO
From the calculation made above, we can see that a higher amount of NO (i.e 1.86 moles) than what was given (i.e 1.79 moles) is needed to react completely with 1.24 moles of NH₃.
Therefore, NO is the limiting reactant and NH₃ is the excess reactant.
Thus, the 1st option gives the correct answer to the question
Answer:
1. NO .
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to identify the limiting reactant by simply calculating the moles of any product, say N2, via the moles of each reactant and including the corresponding mole ratio (4:5 and 6:5):
[tex]1.24molNH_3*\frac{5molN_2}{4molNH_3}=1.55molN_2 \\\\1.79molNO*\frac{5molN_2}{6molNO}=1.50molN_2[/tex]
Thus, since NO yields the fewest moles of N2 product, we infer it is the limiting reactant.
Regards!
Which of the following ionization energies indicates an atom is most likely to gain electrons and form an anion or not form an ion at all?
Group of answer choices
578 kJ/mol
9460 kJ/mol
496 kJ/mol
786 kJ/mol
Answer:
Explanation:
578kj/mol
The compound sodium hydrogen sulfate is a strong electrolyte. Write the reaction when solid sodium hydrogen sulfate is put into water:
Answer:
NaHSO₄(s) --H₂O--> Na⁺(aq) + HSO₄⁻(aq)
Explanation:
Sodium hydrogen sulfate is a strong electrolyte, that is, when dissolved in water it completely dissociates into the cation sodium and the anion hydrogen sulfate. The corresponding chemical equation is:
NaHSO₄(s) --H₂O--> Na⁺(aq) + HSO₄⁻(aq)
Rocks are classified as igneous, metamorphic, or sedimentary according to
Answer:
D. the minerals they contain
Hope this answer is right!!
The table shows the recipe and the available ingredients for making the maximum possible number of sandwiches.
Making Sandwiches
Recipe for One Sandwich:
2 cheese slices, 1 ham slice, 2 bread slices
Ingredients Available:
12 cheese slices, 10 ham slices, 12 bread slices
If the ingredients represent reactants of a chemical reaction, which of the following represents the leftover reactant?
A. 2 ham slices
B. 4 ham slices
C. 2 cheese slices
D. 4 cheese slices
Answer:
B. 4 ham slices
Explanation:
A chemical reaction involves one or more substances known as reactants combining chemically to give one or more substances known as products.
Reactants in chemical reactions combine in definite mole or mass ratios to give products. Therefore, when one substance is present in excess of what is required to combine with another to form products, that substance is known as the excess reagent. The other substance which is present in a smaller amount and which when used up, the reaction stops is known as the limiting reagent.
From the illustration of the sandwiches in the question, the recipe for one sandwich represents the chemical equation of a reaction. The equation form is given below:
2 cheese slices + 1 ham slice + 2 bread slices ---> 1 sandwich
The ratio of the reactant is 2 : 1 : 2
From the available ingredients, 12 cheese slices, 10 ham slices, 12 bread slices.
12 cheese slices will require 6 ham slices and 12 bread slices to produce 6 sandwiches.
However, since there are 10 ham slices, 4 ham slices will be left over unused. This is the excess or leftover reactant.
Answer:
B. 4 ham slices
Explanation:
Got it right on the test
When using vacuum filtration to separate a dissolved solid from an undissolved solid, what techniques should you use to ensure a quantitative separation
Answer: See explanation
Explanation:
Vacuum filtration is referred to as a fast filtration technique that is used in the separation of solids from liquids. It is also used to collect a desired solid. It basically uses a side-arm flask and a Buchner funnel.
Based on the question, the techniques that should be used to ensure a quantitative separation goes thus:
• Wet the filter paper before the mixture is poured into the filter funnel.
• Then, carefully rinse the flask with a little amount of water into the filter funnel.
• After that, the solid on the filter paper should be washed the with a small amount of water.
• Finally, Dry the solid on the filter paper when the separation is done.
A pressure cooker contains 5.68 L of air at a temperature of 390 4K if the absolute pressure of the air in the pressure cooker is 205 Pa how many moles of air are in the cooker
Answer:
3.59x10⁻⁴ mol
Explanation:
Assuming ideal behaviour we can solve this problem by using the PV=nRT formula, where:
P = 205 PaV = 5.68 Ln = ?R = 8314.46 Pa·L·mol⁻¹·K⁻¹T = 390.4 KWe input the data given by the problem:
205 Pa * 5.68 L = n * 8314.46 Pa·L·mol⁻¹·K⁻¹ * 390.4 KAnd solve for n:
n = 3.59x10⁻⁴ molg When aqueous solutions of and are mixed, a solid forms. Determine the mass of solid formed when 140.7 mL of 0.1000 M is mixed with an excess of an aqueous solution of .
The question is incomplete, the complete question is:
When aqueous solutions of NaCl and [tex]Pb(NO_3)_2[/tex] are mixed, a solid forms. Determine the mass of solid formed when 140.7 mL of 0.1000 M NaCl is mixed with an excess of an aqueous solution of
Answer: The mass of lead chloride produced is 1.96 g
Explanation:
Molarity is defined as the amount of solute expressed in the number of moles present per liter of solution. The units of molarity are mol/L. The formula used to calculate molarity:
[tex]\text{Molarity of solution}=\frac{\text{Moles of solute}\times 1000}{ \text{Volume of solution (mL)}}[/tex] .....(1)
Given values:
Molarity of NaCl = 0.1000 M
Volume of the solution = 140.7 mL
Putting values in equation 1, we get:
[tex]0.1000=\frac{\text{Moles of NaCl}\times 1000}{140.7}\\\\\text{Moles of NaCl}=\frac{0.1000\times 140.7}{1000}=0.01407mol[/tex]
The chemical equation for the reaction of NaCl and lead nitrate follows:
[tex]Pb(NO_3)_2(aq)+2NaCl(aq)\rightarrow PbCl_2(s)+2NaNO_3(aq)[/tex]
By the stoichiometry of the reaction:
If 2 moles of NaCl produces 1 mole of lead chloride
So, 0.01407 moles of NaCl will produce = [tex]\frac{1}{2}\times 0.01407=0.007035mol[/tex] of lead chloride
The number of moles is defined as the ratio of the mass of a substance to its molar mass.
The equation used is:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(2)
Molar mass of lead chloride = 278.1 g/mol
Plugging values in equation 2:
[tex]\text{Mass of lead chloride}=(0.007035mol\times 278.1g/mol)=1.96g[/tex]
Hence, the mass of lead chloride produced is 1.96 g
Refer to your completed Table 1d of the recitation guide of ionic compound naming rules to determine whether this statement is true or false. A Roman numeral in a compound name tells you how many of that ion appear in the formula. Select one: True False
Answer:
False
Explanation:
Roman numerals are seen in the names of several compounds. They often appear immediately after the name of central atom in the molecule.
These Roman numerals are used to depict the oxidation state of the central atom in the molecule and not to show how many of that ion appear in the formula.
For instance, in carbon IV oxide, the Roman numeral IV shows that the central atom in the compound-carbon is in the +4 oxidation state.
Having enough folic acid in your system by the early weeks of pregnancy is critical to prevent spina bifida.
Answer:
Yes.
Explanation:
Yes, enough folic acid in the body by the early weeks of pregnancy helps to prevent spina bifida. The body of woman uses folate during the pregnancy which produces red and white blood cells that help your baby to grow. Folate also lowers the risk of neural tube defect (NTD) in the unborn baby. Neural tube defect (NTDs) are the serious birth defects that greatly affect the spinal cord, brain and skull of the baby.
A hot air balloon has an air vent that keeps the air pressure inside and outside the same. Allen observes that a hot air balloon rises up when the gas molecules inside it are heated. Which
of the following laws is used to understand the behavior of the gas and why?
a) The high temperature brings the gas molecules closer together according to Charles's law because this law describes how a gas will behave at constant pressure
b) The high temperature makes the gas molecules spread apart according to Charles's law because this law describes how a gas will behave at constant pressure.
c) The high temperature lowers volume according to Boyle's law because this law describes how a gas will behave when the number of moles remains constant.
d) The high temperature ralses volume according to Boyle's law because this law describes how a gas will behave when the number of moles remains constant.
Answer:
B - The high temperature makes the gas molecules spread apart according to Charles's law because this law describes how a gas will behave at constant pressure.
Explanation:
Charle's Law describes the relationship between temperature and volume, where increased temperature leads to increased volume. When volume is increased, that means the gas molecules are more spread apart and have more random motion. Therefore, the answer is B.
The high temperature causes the gas molecules to spread apart according to Charles's law because explain how a gas, behave at constant pressure.
What does Charles law state?The physical principle called Charles' law which states that the volume of a gas equals a constant value many by its temperature as measured on the Kelvin scale.
Volume regaled by a clinched amount of gas is directly proportional to its temperature and pressure if remains steady.
Thus, option "B" is correct, the volume of a gas equals a constant value.
To learn more about Charles law click here:
https://brainly.com/question/14842720
Gamma rays have the highest frequency among all common electromagnetic radiations. It means the gamma rays have the highest energy and the longest wavelength
Answer:
yes
Explanation:
cos of high electron transfer
Consider the reaction between an alcohol and tosyl chloride, followed by a nucleophile. Write the condensed formula of the expected main organic product.
CH3CH2CH2OH---------- 2.CI 1.TsCl,pyridine__________
Answer:
Consider the reaction between an alcohol and tosyl chloride, followed by a nucleophile. Write the condensed formula of the expected main organic product.
CH3CH2CH2OH---------- 2.CI 1.TsCl,pyridine__________
Explanation:
Given alcohol is propanol.
When it reacts with TsCl, the hydrogen in -OH group is replaced with tosyl group.
Pyridine is a weak base and it neutralizes the HCl (acid) formed during the reaction.
The reaction is shown below:
A molecule or ion that donates the hydrogen in a hydrogen bond is a hydrogen bond donor
a. True
b. False
Answer:
True
Explanation:
Hydrogen bonding is a type of intermolecular interaction that occurs when hydrogen is bonded to a highly electronegative atom.
We define the term ''hydrogen bond donor'' as the molecule that supplies the hydrogen atom in the hydrogen bond.
Hence, it is true that the molecule or ion that donates the hydrogen in a hydrogen bond is a hydrogen bond donor
Dichlorine monoxide, Cl2O is sometimes used as a powerful chlorinating agent in research. It can be produced by passing chlorine gas over heated mercury (II) oxide according to the following equation: HgO + Cl2 ????HgCl2 + Cl2O What is the percent yield, if the quantity of the reactants is sufficient to produce 0.86g of Cl2O but only 0.71 g is obtained?
Answer:
% yield = 82.5%
Explanation:
HgO + 2Cl₂ → HgCl₂ + Cl₂O
Our reactants are:
HgO and Cl₂Our products are:
HgCl₂ + Cl₂OWe do not have information about moles of reactants, but we do know the theoretical yield and the grams of product, in this case Cl₂O, we have produced.
Percent yield = (Yield produced / Theoretical yield) . 100
Theoretical yield is the mass of product which is produced by sufficent reactant. We replace data:
% yield = (0.71 g/0.86g) . 100 = 82.5%
The percent % yield = 82.5%
The balanced chemical equation will be:
HgO + 2Cl₂ → HgCl₂ + Cl₂O
The reactants participating in this reaction are: HgO and Cl₂
The products so formed are: HgCl₂ + Cl₂O
[tex]\text{ Percent yield} = \frac{\text{Yield produced}}{\text{Theoretical yield}} *100[/tex]
The theoretical yield is the maximum possible mass of a product that can be made in a chemical reaction.
[tex]\text{Percent yield}= \frac{0.71 g}{0.86g} * 100 \\\\\text{Percent yield}= 82.5\%[/tex]
Thus, the percent yield is 82.5%.
Learn more:
brainly.com/question/25996347
Calcium has 6 different isotopic forms, listed with their fractional composition values, 40Ca-0.96941; 42Ca-0.00647; 43Ca-0.00135; 44Ca-0.2086 ; 46Ca-0.00004; and 48Ca-0.00187. Identify the most and least abundant isotopes of calcium.
Answer:
The most abundant isotope is ⁴⁰Ca and the least abundant is ⁴⁶Ca
Explanation:
The mass, in percentage, of eah isotope of Calcium is their fractional composition multiplied by 100:
40Ca-0.96941*100 = 96.941% of ⁴⁰Ca
42Ca-0.00647*100 = 0.647% of ⁴²Ca
43Ca-0.0013*100 = 0.13% of ⁴³Ca
44Ca-0.02086*100 = 2.086% ⁴⁴Ca
46Ca-0.00004*100 = 0.004% ⁴⁶Ca
48Ca-0.00187*100 = 0.187% of ⁴⁸Ca
That means the most abundant isotope is ⁴⁰Ca and the least abundant is ⁴⁶Ca
Which of the following could not be a resonance structure of CH3NO2?
a)
H
H-C-NO
H
b)
H .0:
H-C-N
H
c)
H:03
H-C-NC2
H:06
d)
H
H-C=N
H :9-H
e) Both c and d
Answer:
the answer is b.CH3NO2 I guess I'm correct
which of these molecules is nonpolar?
Answer:
option b is your right answer
a polluted lake is 0.300 μg (micrograms) per liter of water, what is the total mass of mercury in the lake, in kilograms, if the lake has a surface area of 15.0 square miles and an average depth of 27.0 feet?
Answer:
95.9 kg
Explanation:
First we convert 15.0 mi² to m²:
15.0 mi² * ([tex]\frac{1609.34 m}{1mi}[/tex])² = 3.88x10⁷ m²Then we convert 27.0 ft to m:
27.0 ft * [tex]\frac{0.3048m}{1ft}[/tex] = 8.23 mNow we calculate the total volume of the lake:
3.88x10⁷ m² * 8.23 m = 3.20x10⁸ m³Converting 3.20x10⁸ m³ to L:
3.20x10⁸ m³ * [tex]\frac{1000L}{1m^3}[/tex] = 3.20x10¹¹ LNow we calculate the total mass of mercury in the lake, using the given concentration:
0.300 μg / L * 3.20x10¹¹ L = 9.59x10¹⁰ μgFinally we convert μg to kg:
9.59x10¹⁰ μg * [tex]\frac{1kg}{1x10^9ug}[/tex] = 95.9 kgcalculate the maximum theoretical percent recovery from the recrystallization of 1.00g of benzoic acid
Answer:
The maximum theoretical percent recovery from the recrystallization of 1.00 g of benzoic acid from 15 mL of water = 94.9%
Note: The question is incomplete. A similar but complete question is given below:
The solubility of benzoic acid in water is 6.80g per 100mL at 100 degrees C and 0.34 g per 100mL at 25 degrees C.
Calculate the maximum theoretical percent recovery from the recrystallization of 1.00 g of benzoic acid from 15 mL of water, assuming the solution is filtered at 25 degrees C.
Explanation:
Solubility of benzoic acid in water at 100 degrees C = 6.80g per 100mL
Solubility of benzoic acid in water at 25 degrees C = 0.34 g per 100mL
Mass of benzoic acid to be theoretically recovered from 100 mL of water = 6.80 g - 0.34 g = 6.46 g
At 25 degrees;
0.34 g of benzoic acid is present in 100 mL of water
x g of benzoic acid will be present in 15 mL of water
x = 0.34 × 15 / 100 = 0.051 g
Mass of benzoic acid to be theoretically recovered from 25 mL of water = 1.00 g - 0.051 g = 0.949 g
Maximum theoretical percent recovery = (mass recovered / original mass dissolved) x 100%
Maximum theoretical percent recovery = (0.949 / 1.00) × 100% = 94.9 %
Therefore, the maximum theoretical percent recovery from the recrystallization of 1.00 g of benzoic acid from 15 mL of water = 94.9%