CHM 203 CBT PRACTICE TEST

1.

The reactions with the high value of energy of activation are

2.

A beaker with a mixture of ice and water is maintained at equilibrium: H2O(s) + heat➡️H2O(l); If the temperature of the system is decreased:

3.

Rusting of iron Is an example of________ reaction

4.

Milk sours more rapidly in summer than in winter because

5.

In a reaction in which the rate of the reverse reaction is equal to the rate of the forward reaction, a state of ____________ is attained.

6.

Which of the following involves a decrease in entropy?

7.

Which reaction is likely to have a negative change in entropy?

8.

Calculate the standard entropy change for the following reaction, 2 Ag2O(s) ➡️4 Ag(s) + O2(g)

given S^{o}[Ag2O] = 121.3 J/K·mol, S^{o}[Ag(s)] = 42.6 J/K·mol, and S^{o}[O2(g)] = 205.1 J/K·mol.

9.

The minimum additional energy, above the average internal energy, which the reacting molecules must possess so that their collision result in a reaction is known as

10.

All of the following processes lead to an increase in entropy EXCEPT

11.

For a reaction: 2H2+ 2NO ➡️2H2O + N2 the rate law is R = K [H2][NO]^2 The Order of the reaction is?

12.

In the reaction: 2B ➡️Product; the rate equation is: Rate = k[B]. If the concentration of is doubled, the rate of reaction will increase by a multiple of

13.

Which of the following expressions is associated with the law of conservation of energy?

14.

A reaction with a negative value of 🔼G is said to be

15.

All of the following statements concerning entropy are true EXCEPT

16.

In a reaction: 2A ➡️B + 2C, which of the statement is true?

17.

Predict the signs of 🔼H and 🔼S for the evaporation of water at 35 ^oC.

18.

Which of the following statements about the kinetics of the reaction H2(g) + Br2(g) ➡️2HBr(g) is definitely true?

19.

Every type of chemical bond contains a certain amount of energy. The total bond energy, which is essentially equivalent to the total potential energy of the system, is a quantity known as:

20.

Thermodynamics can be used to determine all of the following EXCEPT

21.

The heat of combustion for 1 mole of carbon to carbon dioxide is -410 kJ. How many kJ of heat would be liberated from the complete combustion of 60.0 g of carbon?

22.

The temperature remains constant as energy is added to a substance. How may the substance be changing?

23.

Which of the following statements about enthalpy is incorrect?

24.

If the reaction A + B C has an equilibrium constant greater than one, which of the following statements is correct?

25.

A statement of the second law of thermodynamics is that

26.

If a process is exothermic and not spontaneous, then what must be true?

27.

If a chemical reaction has a positive change in entropy, 🔼S, then

28.

Which of these followings would lead to an increase in the internal energy of a system?

29.

Calculate the standard entropy change for the following reaction, 2Ag2O(s) ➡️4 Ag(s) + O2(g); given S^{o}[Ag2O] = 121.3 J/K·mol, S^{o}[Ag(s)] = 42.6 J/K·mol, and S^{o}[O2(g)] = 205.1 J/K·mol.

30.

Of the following product-favoured processes, which are endothermic? 1. the combustion of methane to produce water and carbon dioxide. 2. the expansion of an ideal gas. 3. the melting of ice at temperatures greater than 0ºC.

31.

When extra NH3 is added to the following system at equilibrium: 3H2(g) + N2(g) ➡️ 2 NH3(g), what happens?

32.

The common-ion effect

33.

The reactions catalyzed by sunlight are called ____________ reactions

34.

The first law of thermodynamics deals with

35.

If a gas absorbs 1000 J of heat and expands by 0.5 $dm^{3}$ against a constant pressure of 4 atms (1 atm = 100000 Pa), then the change in internal energy is approximately

36.

Which of these is true of an isochoric system?

37.

One mole of an ideal gas is heated at a constant pressure of 101300 N $m^{2}$, from 273.2 K to 373 K. Calculate the work involved R = 8.314 J/mol/K).

38.

Powdered marble reacts more rapidly with HCl than the chips of marble because:

39.

The specific heat of silver is 0.0565 $cal/g/^{o}C$. Assuming no loss of heat to the surroundings or to the container, calculate the final temperature when 100 g of silver at 40 $^{o}C$ is immersed in 60 g of water at 10 $^{o}C$.