1-◇Formed with NaOH, HCl, NH3 and H2CO3 acids and bases; I. NaCl, II. Na2CO3, III. NH4Cl Which or which salts hydrolysis?
a) I only b) II only c) III only d) I and II e) II and III
2-◇H2 (g) + CO2 (g) <----> H2O (g) + CO (g) K1 2CO (g) + O2 (g) <----> 2CO2 (g) K2 Since there is 2H2O (g) <----- What is the equilibrium constant of the reaction of> 2H2 (g) + O2 (g) in terms of K1 and K2?
a) K1^2xK2
b) 2K1 + K2
c) -2K1-K2
d) 1 / K1^2xK2
e) 1 / 2K1xK2
3-◇In a chemical reaction; (A) changes the mechanism, does not affect ΔH, (B) Mechanism and does not change the rate constant, it affects the reaction rate, (C) Changes the rate constant and speed. Which of the following is true for A, B and C?
a)Catalyst Concentration Temperature b)Temperature Concentration Catalyst
c) Catalyst Temperature Concentration d)Concentration Catalyst Temperature e)Temperature Catalyst Concentration
1-◇Formed with NaOH, HCl, NH3 and H2CO3 acids and bases; I. NaCl, II. Na2CO3, III. NH4Cl Which or which salts hydrolysis?
a) I only b) II only c) III only d) I and II e) II and III
The answer is e but DO YOU KNOW WHY? It doesn't help you for me to give you the answer if you can't do a hydrolysis problem on your own.
2-◇H2 (g) + CO2 (g) <----> H2O (g) + CO (g) K1 2CO (g) + O2 (g) <----> 2CO2 (g) K2 Since there is 2H2O (g) <----- What is the equilibrium constant of the reaction of> 2H2 (g) + O2 (g) in terms of K1 and K2?
a) K1^2xK2
b) 2K1 + K2
c) -2K1-K2
d) 1 / K1^2xK2
e) 1 / 2K1xK2
The answer is a but do you know why? Can you do one of these on your own?
I don't understand question 3.
In 3 question
Which of these options do they define as A, B and C definitions?
a)Catalyst, Concentration, Temperature
b)Temperature, Concentration, Catalyst
c) Catalyst ,Temperature, Concentration
d)Concentration, Catalyst ,Temperature
e)Temperature, Catalyst, Concentration
No help. I still don't get 3.
Thank you so much 🤗
1- To determine which salts undergo hydrolysis, we need to understand the concept of hydrolysis and how different salts behave when dissolved in water. Hydrolysis is a chemical reaction in which water molecules react with the ions of a salt, leading to the formation of either acidic or basic solutions.
In this case, we have four salts: NaCl, Na2CO3, NH4Cl.
To determine which salts undergo hydrolysis, we can look at the nature of the cation and anion in each salt.
- NaCl: Sodium chloride is a neutral salt formed from a strong base (NaOH) and a strong acid (HCl). Neither the cation (Na+) nor the anion (Cl-) will undergo hydrolysis. Therefore, NaCl does not undergo hydrolysis.
- Na2CO3: Sodium carbonate is formed from a strong base (NaOH) and a weak acid (H2CO3). The carbonate ion (CO3^2-) can react with water, forming the bicarbonate ion (HCO3-) and hydroxide ion (OH-). Therefore, Na2CO3 undergoes hydrolysis.
- NH4Cl: Ammonium chloride is formed from a weak base (NH3) and a strong acid (HCl). The ammonium ion (NH4+) can act as an acid and react with water, producing hydronium ions (H3O+). Therefore, NH4Cl undergoes hydrolysis.
Based on this analysis, the salts that undergo hydrolysis are: Na2CO3 (II) and NH4Cl (III).
Therefore, the answer is e) II and III.
2- We are given two chemical reactions and their equilibrium constants:
1) H2 (g) + CO2 (g) ⇌ H2O (g) + CO (g) K1
2) 2CO (g) + O2 (g) ⇌ 2CO2 (g) K2
We are asked to find the equilibrium constant for the reaction: 2H2 (g) + O2 (g) ⇌ ???
To solve this, we need to use the concept of equilibrium constants. When reactions are added together, the equilibrium constants are multiplied.
The given reaction involves the first reaction in reverse and the second reaction in the forward direction. Therefore, we need to consider the reverse equilibrium constant for the first reaction and the forward equilibrium constant for the second reaction.
The reverse reaction of the first reaction has the equilibrium constant: 1/K1
The forward reaction of the second reaction has the equilibrium constant: K2
When we add these two reactions together, the equilibrium constant is obtained by multiplying these equilibrium constants:
(1/K1) * K2 = K2/K1
Therefore, the equilibrium constant of the reaction: 2H2 (g) + O2 (g) is K2/K1.
The answer is d) 1/K1^2 * K2.
3- The question asks about the effects of three factors on the mechanism, ΔH (enthalpy change), and the rate constant (k) in a chemical reaction. Let's analyze each answer choice:
a) Catalyst Concentration Temperature:
- A catalyst alters the mechanism of a reaction by providing an alternative reaction pathway with lower activation energy. It does not directly affect ΔH or the rate constant. Therefore, this choice is incorrect.
b) Temperature Concentration Catalyst:
- Increasing temperature generally increases the reaction rate by providing more kinetic energy to the reactant molecules, but it does not affect the mechanism or the rate constant. Changing the concentration of reactants may influence the reaction rate, but it does not impact the mechanism or the rate constant. Therefore, this choice is incorrect.
c) Catalyst Temperature Concentration:
- This choice correctly identifies that a catalyst affects the rate constant, but it does not affect the temperature or concentration. Therefore, it is incorrect.
d) Concentration Catalyst Temperature:
- Similar to the previous choices, this combination does not accurately represent the effects of A, B, and C. Concentration and temperature can affect the reaction rate, but not the mechanism or rate constant. Therefore, this choice is incorrect.
e) Temperature Catalyst Concentration:
- This choice accurately represents the effects of A, B, and C. Temperature affects the rate constant, a catalyst alters the mechanism, and changing the concentration can influence the reaction rate. Therefore, this choice is correct.
The answer is e) Temperature Catalyst Concentration.