Answer:
1.88 A
Explanation:
Let's consider the reduction of copper in an electrolytic cell.
Cu²⁺ + 2 e⁻ ⇒ Cu
We can calculate the charge used to deposit 12.3 g of Cu using the following relations.
The molar mass of Cu is 63.55 g/mol.1 mole of Cu is deposited when 2 moles of electrons circulate.1 mole of electrons has a charge of 96486 C (Faraday's constant).The charge used is:
[tex]12.3 g \times \frac{1 molCu}{63.55gCu} \times \frac{2molElectron}{1molCu} \times \frac{96486C}{1molElectron} = 3.73 \times 10^{4} C[/tex]
We can convert 5.50 h to seconds using the conversion factor 1 h = 3600 s.
5.50 h × 3600 s/1 h = 1.98 × 10⁴ s
The current used is:
I = q/t = 3.73 × 10⁴ C/1.98 × 10⁴ s = 1.88 A
what is the qualitative analysis of (nh4) 2co3 using NaOH, HCL, BaCL2, and AgNO3
Answer:
qualatatiev is fs-hj_jakakak
Complete and balance the equations for the given single displacement reactions. Write the reaction in molecular form. Phases are optional. If you need to clear your work and reset the equation, click the CLR button.Li(s) + H2O---------- Ca(s) + H2O ---------------
Answer:
Li(s) + H2O(l) -----> LiOH(aq) + H2(g)
Ca(s) + 2H2O(l) ---------------> Ca(OH)2(aq) + H2(g)
Explanation:
Metals react with water to yield the metal hydroxide and hydrogen gas as shown in the answer above.
The reaction equations were balanced, the number of atoms of each element on both side of the reaction equation is exactly the same.
This is the way to write a balanced reaction equation for the species shown in the question.
For each pair of elements, indicate which one you would expect to have the greater electron affinity (E.A.) (i.e. mathematically this means the more negative value of EA):
The question is incomplete, the complete question is shown in the image attached to this answer
Answer:
1) K
2) F
3) Si
4) Br
Explanation:
If an element has a more negative value of electron affinity, then it has a greater ability to attract an electron.
In each of the following pairs of elements, one element has a more negative electron affinity for certain reasons.
Between K and Ca, the incoming electron in K goes into a 4s orbital which is lower in energy and more stable. For Ca, the electron goes into a 3d orbital which is more unstable.
Between Ne and F, Ne already has a filled outermost shell hence the incoming electron goes into the higher energy 3s level. In F, the electron goes into the 2p level and completes it. Hence F has a more negative electron affinity.
Let us recall that half filled and completely filled orbitals are exceptionally stable. Hence, the electron affinity of Si is more negative than that of P because in P, the electron goes into an exceptionally stable half filled orbital.
Recall that the more the value of Zeff, the more negative the electron affinity hence electron affinity increases across a period; hence, Br has a more negative value of electron affinity than Se.
What is the molarity of an HCl solution if 43.6 mL of a 0.125 M NaOH solution are needed to titrate a 25.0 mL sample of the acid according to the equation below (show your calculations)? NaOH(aq) + HCl(aq) → H2O(l) + NaCl(aq)
Answer: The molarity of an HCl solution is 0.218 M if 43.6 mL of a 0.125 M NaOH solution are needed to titrate a 25.0 mL sample of the acid.
Explanation:
Given: [tex]V_{1}[/tex] = 43.6 mL, [tex]M_{1}[/tex] = 0.125 M
[tex]V_{2}[/tex] = 25.0 mL, [tex]M_{2}[/tex] = ?
Formula used to calculate the concentration of acid is as follows.
[tex]M_{1}V_{1} = M_{2}V_{2}[/tex]
Substitute the values into above formula.
[tex]M_{1}V_{1} = M_{2}V_{2}\\0.125 M \times 43.6 mL = M_{2} \times 25.0 mL\\M_{2} = 0.218 M[/tex]
Thus, we can conclude that the molarity of an HCl solution is 0.218 M if 43.6 mL of a 0.125 M NaOH solution are needed to titrate a 25.0 mL sample of the acid.
The molarity of the HCl solution used in the neutralization reaction has been 0.218 M.
The reaction of NaOH with HCl has been a neutralization reaction. The resultant will be salt and water.
In the reaction the molarity can be calculated as:
Molarity of HCl [tex]\rm[/tex][tex]\times[/tex] Volume of HCl = Molarity of NaOH
Given,
The volume of HCl solution = 25 ml
Molarity of NaOH = 0.125 M
Volume of NaOH solution = 43.6 ml
Substitute the values in the equation:
Molarity of HCl [tex]\times[/tex] 25 = 0.125 [tex]\times[/tex] 43.6
Molarity of HCl [tex]\times[/tex] 25 = 5.45
Molarity of HCl solution = [tex]\rm \dfrac{5.45}{25}[/tex]
Molarity of HCl solution = 0.218 M
The molarity of the HCl solution used in the neutralization reaction has been 0.218 M.
For more information about the molarity, refer to the link:
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Give the symbol for an element that is:__________
a. a halogen: _______________
b. an alkali metal: _______________
c. a noble gas: _______________
d. an alkaline earth metal : ____________
a. Br, Cl, F
b. Na, K, Ba
c. He, Ar, Ne
d. Ca, Ba, Mg
Answer:
a. halogen : F ,Cl ,Br l ,At
b an alkali metal: Na,Li, Rb, Cs
c. a noble gas: He, Ne, Kr, Ar
d. an alkaline earth metal: Be,Mg,Ca, Sr
hope it helps
stay safe healthy and happy...Which of the following represents a compound?
Na
CO2
Со
Mn
Answer:
CO2
Explanation:
Carbon dioxide is a chemical compound that consists of two oxygen atoms and one carbon atom
Determine whether the stopcock should be completely open, partially open, or completely closed for each activity involved with titration.
Close to the calculated endpoint of a titration ________
At the beginning of a titration _______
Filling the buret with titrant ________
Conditioning the buret with titrant _______
Answer:
Close to the calculated endpoint of a titration - Partially open
At the beginning of a titration - Completely open
Filling the buret with titrant - Completely closed
Conditioning the buret with the titrant - Completely closed
Explanation:
'Titration' is depicted as the process under which the concentration of some substances in a solution is determined by adding measured amounts of some other substance until a rection is displayed to be complete.
As per the question, the stopcock would remain completely open when the process of titration starts. After the buret is successfully placed, the titrant is carefully put through the buret in the stopcock which is entirely closed. Thereafter, when the titrant and the buret are conditioned, the stopcock must remain closed for correct results. Then, when the process is near the estimated end-point and the solution begins to turn its color, the stopcock would be slightly open before the reading of the endpoint for adding the drops of titrant for final observation.
The action of some commercial drain cleaners is based on the following reaction:
2 NaOH(s) + 2 Al(s) + 6 H2O(l) â 2 NaAl(OH)4(s) + 3 H2(g)
What is the volume of H2 gas formed at STP when 4.32 g of Al reacts with excess NaOH?
A. 3.59 L
B. 2.39 L
C. 5.87 L
D. 5.38 L
Answer:
5.38 L
Option D.
Explanation:
2 NaOH(s) + 2 Al(s) + 6 H₂O(l) → 2 NaAl(OH)₄(s) + 3 H₂(g)
We convert mass of Al to moles:
4.32 g . 1 mol /26.98g = 0.160 moles
As NaOH is in excess, aluminum is the limiting reactant.
We see stoichiometry, were ratio is 2:3.
2 moles of Al can produce 3 moles of hydrogen
Our 0.160 moles may produce (0.160 . 3)/2 = 0.240 moles of H₂.
We know that 1 mol of any gas at STP conditions is contained in 22.4L
So let's make the conversion factor:
0.240 mol . 22.4L / 1mol = 5.38 L
What effect does a high carbon level have on a deep ocean
Explanation:
High carbon concentration in the deep ocean means increased absorption of carbon to the atmosphere resulting to even greater and harmful amounts of carbon in the atmosphere. Therefore we need to keep a close eye of the deep ocean in the quest to monitor and pump out excess carbon from this part of marine life.
A 3.0-liter sample of an ideal gas is at a pressure of 2.5 atm at 15oC. (i) How many moles of gas are in the sample? (ii) If the volume does not change, what is the pressure of the gas when the temperature is 50oC?
Explanation:
here are the answers. Note that because the pressure is constant, you can use Gay Lussac's formula
Which of the following is an alkaline earth metal?
A Carbon
B aluminum
C magnesium
D silicon
Answer:
Magnesium.
Explanation:
Because it is in group II
Which of the following statements is correct concerning the reaction 2 A + B → 2 C + 2 D?
1. The reaction is second-order overall
2. The reaction is third order overall
3. The rate is equal to k[A]²[B]
4. The rate is equal to k[A][B]
5. It cannot be determined given this information
Answer:
2.The reaction is third order overall
Explanation:
THIS ANSWER IS CORRECT
MARK ME AS BRAINLIEST
Which of the following is a physical change?
A sealed container was filled with 0.300mol H2(g), 0.400mol I2(g), and 0.200mol HI(g) at 870K and total pressure 1.00bar. Calculate the amounts of the components in the mixture at equilibrium given that K.= 70 for the reaction H2(g)+I2(g) --> 2HI(g).
Answer:
[HI] = 0.704mol
[H2] = 0.048mol
[I2] = 0.148mol
Explanation:
Based on the equilibrium:
H2(g)+I2(g) --> 2HI(g)
The equilibrium constant, K, is defined as:
K = 70 = [HI]² / [H2] [I2]
Where [] could be taken as the moles in equilibrium of each reactant
To know the direction of the equilibrium we need to find Q with the initial moles of each species:
Q = [0.200mol]² / [0.300mol] [0.400mol]
Q = 0.333
As Q < K, the reaction will shift to the right producing more HI. The equilibrium moles are:
[HI] = 0.200mol + 2X
[H2] = 0.300mol - X
[I2] = 0.400mol - X
Replacing in K:
70 = [0.200 + 2X ]² / [0.300 - X] [0.400 - X]
70 = 0.04 + 0.8 X + 4 X² / 0.12 - 0.7 X + X²
8.4 - 49 X + 70 X² = 0.04 + 0.8 X + 4 X²
8.36 - 49.8X + 66X² = 0
Solving for X:
X = 0.252 moles. Right solution
X = 0.502 moles. False solution. Produce negative moles.
Replacing:
[HI] = 0.200mol + 2*0.252 mol
[H2] = 0.300mol - 0.252 mol
[I2] = 0.400mol - 0.252 mol
[HI] = 0.704mol
[H2] = 0.048mol
[I2] = 0.148mol
Arrange aluminum, boron, nitrogen, and phosphorous in order of increasing electronegativity.
a. Al < N < P < B
b. Al < B < P < N
c. N < P < B < Al
d. B < Al < N < P
Answer:
Option b.
Al < B < P < N
Explanation:
Electronegativity is the capacity of an atom to attract electrons.
Usually, if we look at the periodic table, the elements in the left are the ones with the least electronegativity, and as we go to the right, the electronegativity increases (this is not really exact)
There are a lot of tables of electronegativity that can be used here, we can find that:
element: electronegativity:
N 3.04
B 2.04
P 2.19
Al 1.61
So, the order from least to greatest is:
Al, B, P, N
Then the correct option is:
b: Al < B < P < N
What is the density of Ar(g) at -11°C and 675 mmHg?
Answer:
The Density Of Ar (g) At -11°C And 675 MmHg (R =0.08206 L·atm/mol·K, 1 Atm = 760mmHg).
After standardizing a NaOH solution, you use it to titrate an HCl solution known to have a concentration of 0.203 M. You perform five titrations and obtain the following results: 0.210, 0.204, 0.201, 0.202, and 0.197 M. a) What is the mean
Answer:
0.203 is the mean of the concentration of the HCl solution
Explanation:
You have 5 concentrations. The most appropiate result is the mean of those results. The mean is a statistical defined as the sum of each result divided by the total amount of results. For the results of the problem, the mean is:
0.210 + 0.204 + 0.201 + 0.202 + 0.197 = 1.014 / 5 =
0.203 is the mean of the concentration of the HCl solutionimportant of organic chemistry in our daily life
Answer:
Human life has become very simple by using organic chemicals. The importance of organic chemicals in the daily life and industrial area can be explained as follows. (i) Food Vitamins, proteins, sugar, flour, fats etc. ... (ii) Agriculture is an important place for organic chemical for the growth of agricultural production.
The angular momentum quantum number (l) value of 0 indicates the ________ subshell.
Answer:
indicates the number of subshells
What occurs in endothermic reactions?
a) Heat energy is absorbed.
b) Water is produced.
c) Oxygen is produced.
d) Heat energy is released.
Answer:
a) Heat energy is absorbed.
Explanation:
What occurs in endothermic reactions?
a) Heat energy is absorbed. YES. This is the definition of an endothermic reaction.
b) Water is produced. NO. Endothermic refers to the heat absorbed and not to the products formed.
c) Oxygen is produced. NO. Endothermic refers to the heat absorbed and not to the products formed.
d) Heat energy is released. NO. This is known as an exothermic reaction.
Question 5: Energy Sources (12 points)
A. There are many ways to produce electricity. List two energy sources that generate electricity via a chemical reaction, and explain what kind of reaction each uses. (6 points)
B. Ethane is a common component of energy sources. Write the chemical formula for ethane. (2 points)
C. Write and balance the chemical equation for the combustion reaction of ethane. (4 points)
Answer:
See explanation
Explanation:
It is possible to generate electricity through a chemical reaction in two ways;
I) use of a voltaic cell where spontaneous chemical processes produce electrical energy.
ii) use of an electrolytic cell where non spontaneous chemical processes produce electrical energy.
The chemical formula of ethane is C2H6
The balanced chemical equation for the combustion of ethane is as follows;
C2H6 + 7/2 O2 ------> 2CO2 + 3H2O
Will give brainliest answer please give explanation
33.5 cs=_________s
Answer: 3.4 × 10 -1 equal 33.5 cs. May I have brainiest? pls. (the -1 is to the power of the ten.
What does the "R-" represent?
A. a halogen
B. a hydroxyl group
C. an alkyl group
D. an oxyacid
URGENT!!
Answer:
general formula RCOX, where R represents an alkyl or aryl organic radical group, CO ... represents a halogen atom such as chlorine ... loss of a hydroxyl group (-OH), viz, acetyl,. CH, CO- ..
Water has a density of 1.00 g/mL. If you put an object that has a density of 0.79 g/mL into water, it will sink to the
bottom.
ANSWER:
True
False
Answer:
False
Explanation:
An object with a density greater than 1.00g/mL (greater than the density of water) will sink. An object with a density less than the density of water, will float.
If the water has a density of 1.00 g/mL. If you put an object that has a density of 0.79 g/mL into water, it will sink to the bottom, this statement is false.
What is density?The density of an actual content is its mass per unit volume. The most common symbol for density is d, but the Latin letter D can also be used.
Three of an object's most fundamental properties are mass, volume, and density. Mass describes how heavy something is, volume describes its size, and density is defined as mass divided by volume.
The density of something is a measure of how heavy it is in relation to its size. When an artifact is more dense than water, it plunges; when an object is less dense than water, it floats.
Density is a property of a substance that is independent of the amount of substance.
As in the given scenario, water is having density 1 g/mL and object in having density less then it so it will float on water.
Thus, the given statement is false as the material will not sink, rather it will float on water.
For more details regarding density, visit:
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Consider the following reaction at equilibrium. What effect will decreasing the temperature have on the system? DH=+890kJCO2(g)+2H2O(l)<--> CH4(g)+2O2(g)a) the equilibrium constant will increaseb) the reaction will shift to the left in the direction of the reactantsc) the reaction will shift to the right in the direction of the productsd) no effect will be observed
Answer:
Option B. The reaction will shift to the left in the direction of the reactants.
Explanation:
The equation for the reaction is given below:
CO₂ + 2H₂O <=> CH₄ + O₂
Enthalpy change (ΔH) = +890 KJ
The reaction illustrated by the equation is endothermic reaction since the enthalpy change (ΔH) is positive.
Increasing the temperature of an endothermic reaction will shift the equilibrium position to the right and decrease the temperature will shift the equilibrium position to the left.
Therefore, decreasing the temperature of the system illustrated by the equation above, will shift the reaction to the left in the direction of the reactants.
Thus, option B gives the right answer to the question.
The elemental mass percent composition of succinic acid is 40.68% CC, 5.12% HH, and 54.19% OO. Determine the empirical formula of succinic acid.
Answer:
C2H3O2
Explanation:
Empirical formula is defined as the simplest whole-number ratio of atoms present in a molecule. To solve this question we need to convert the percentage of each atom to moles using molar mass. With the moles of each atom we can find the ratio:
Moles C -Molar mass: 12.01g/mol-
40.68g * (1mol/12.01g) = 3.387 moles C
Moles H-Molar mass:1g/mol-:
5.12g * (1mol/1g) = 5.12 moles H
Moles O -Molar mass: 16g/mol-
54.19g * (1mol/16g) = 3.387 moles O
Ratio of atoms (Dividing in moles of C that are the lower number of moles):
C = 3.387 moles C / 3.387moles C = 1
H = 5.12moles H / 3.387moles C = 1.5
O = 3.387moles O / 3.387 moles C = 1
This ratio twice (To have only whole-numbers):
C = 2
H = 3
O = 2
Empirical formula of succinic acid:
C2H3O2he equation for the dissociation of pyridine is
C5H5N(aq) + H2O(l) ⇌ C 5H5NH+(aq) + OH-(aq) Kb = 1.9 × 10-9
Calculate the pH of a pyridine solution that has a concentration of 9.2 M. Round your answer to two decimal places.
Answer:
10.10
Explanation:
Step 1: Write the basic dissociation reaction for pyridine
C₅H₅N(aq) + H₂O(l) ⇌ C₅H₅NH⁺(aq) + OH⁻(aq) Kb = 1.9 × 10⁻⁹
Step 2: Calculate [OH⁻]
For a weak base, we will use the following expression.
[OH⁻] = √(Cb × Kb) = √(9.2 × 1.9 × 10⁻⁹) = 1.3 × 10⁻⁴ M
Step 3: Calculate pOH
We will use the definition of pOH.
pOH = -log [OH⁻] = -log 1.3 × 10⁻⁴ = 3.9
Step 4: Calculate pH
We will use the following expression.
pH = 14 - pOH = 14 - 3.9 = 10.10
Mava=mbvb ma x5.0ml = 5.2ml x 0.10m
Answer:
[tex]M_{a}[/tex] = 0.104 m
Explanation:
This expression is used to determine either the mass or volume of an acid or a base used during titration process.
So that;
[tex]M_{a}[/tex][tex]V_{a}[/tex] = [tex]M_{b}[/tex][tex]V_{b}[/tex]
[tex]M_{a}[/tex] is the mass of the acid
[tex]V_{a}[/tex] is the volume of the acid
[tex]M_{b}[/tex] is the mass of the base
[tex]V_{b}[/tex] is the volume of the base
Given that:
[tex]M_{a}[/tex] x 5.0 m l = 5.2 ml x 0.10 m
[tex]M_{a}[/tex] x 5.0 = 0.52 m
[tex]M_{a}[/tex] = [tex]\frac{0.52}{5.0}[/tex]
= 0.104
[tex]M_{a}[/tex] = 0.104 m
The mass of the acid used is 0.104 m.
Question 6: Energy Use (8 points)
A. The electricity supply of a certain U.S. state needs to be increased. The state is very cloudy and rainy from October to April. There are several large rivers, and there are almost no areas with high winds due to heavy forest cover. Several sources of underground heat are available. The state also has a surplus of organic waste.
i. Name two renewable energy sources, and state and explain whether or not the state should use them based on the description above. (6 points)
ii. If the state wants to minimize environmental damage, what energy sources should it consider using? Explain your position. (2 points)
Answer:
somebody small boy is not w e a r d
z0 0m = 257 473 5835 p c:- 12 34
why do the Philippines have generally warm temperature throughout the year?a. it is near the sun b.it has many volcanoes c. it lies near the equator d. it has many islands.what is the correct answer?
Answer:
F. When everyone is together it gets hotter
Explanation:
Answer:
c. it lies near the equator
