Please check attached files.

Unit2 test is much shorter than other 2 units. (there’s only 19 multiple choice questions and 5 short answer questions)

Short answer questions doesn’t need to be long. Few sentences with clear explanation is enough.

CHM 12 Unit 2 Test
Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
____ 18. Consider the following four equations:
1. C6H6(l) + 15/2 O2(g)  6CO2(g) + 3H2O(l) )H1
2. H2(g) + 1/2 O2(g)  H2O(l) H2
3. C(s) + O2(g)  CO2(g) H3
4. 6C(s) + 3H2(g)  C6H6(l) H4

The enthalpy change for reaction 1, H1 can be obtained by combining the H’s for the other reactions in which of the following ways?
a. 6(H3) + 3(H2) + H4 d. 6(H3) + 3(H2) – H4
b. 6(H3) – 3(H2) + H4 e. none of the above
c. 6(H3) – 3(H2) + H4
____ 19. For which one of the following substances is the standard enthalpy of formation, Hf, equal to zero?
a. water [H2O(l)] d. carbon dioxide [CO2(g)]
b. lead [Pb(s)] e. tin [Sn(g)]
c. carbon dioxide [CO2(s)]

____ 23. Use the following data to determine the of vaporization for silicon tetrachloride at its boiling point.

a. –30.6 kJ d. +609.6 kJ
b. +30.6 kJ e. +1249.8 kJ
c. –609.6 kJ
____ 24. A small 2.0-g candle is consumed in heating 100 g of water from 25ºC to 75ºC. If two of the same candles are used to heat 200 g of water, the temperature of the water after heating would have changed by
a. 25ºC d. 100ºC
b. 50ºC e. 150ºC
c. 75ºC
____ 25. A small 2.0-g candle is consumed in heating 100 g of water from 25ºC to 75ºC. If you ignore loss of heat to the air, the energy produced per gram of the candle would be
a. 8.56 kJ d. 2.62 kJ
b. 5.23 kJ e. 20.65 kJ
c. 10.46 kJ
____ 26. Methyl alcohol both burns and evaporates. Use this information to determine which of these statements is false.
a. the burning of methyl alcohol is an exothermic process
b. the intermolecular forces of methyl alcohol are weaker than the intramolecular forces
c. more heat is involved in burning methyl alcohol than in evaporating a mole of alcohol
d. the evaporation of methyl alcohol is an exothermic process
e. methyl alcohol can evaporate at temperatures below its boiling point
____ 27. The combustion of magnesium in air is very exothermic.

If the given two reactions and their heats of reaction were used to determine the heat of combustion of magnesium the result would be
a. x + y d. x – 2y
b. x – y e. not enough information is given
c. 2x – y
____ 28. What is the range of the enthalpy change for a nuclear reaction?
a. d.
b. e.
c.
____ 29. What is the range of the enthalpy change for a chemical reaction?
a. d.
b. e.
c.
____ 30. A rate of reaction is usually obtained by measuring
a. the rate at which products are consumed
b. the rate at which reactants are produced
c. the rate at which reactants are consumed
d. the temperature of the solution
e. the mass and volume of the products
____ 31. In the reaction, , if the concentration changes from 0.45 mol/L to 1.00 mol/L in 2 minutes, what is the overall rate of production of nitrogen dioxide in the system?
a. 3.64 mol/(L•min) d. 12.6 mol/(L•min)
b. 0.275 mol/(L•min) e. 0.333 mol/(L•min)
c. 0.137 mol/(L•min)
____ 32. What property would be appropriate to measure the reaction rate in the reaction between magnesium and hydrochloric acid?
a. change in conductivity d. change in pressure
b. change in mass e. change in volume
c. change in colour
____ 33. Which of the following is not a factor that controls the rate of the reaction
a. chemical nature of the reactants d. surface area
b. concentration of the reactants e. temperature
c. the number of products formed
____ 34. Generally, temperature affects the rate of a reaction in which of the following ways?
a. increasing the temperature reduces the rate of the reaction
b. decreasing the temperature decreases the rate of the reaction
c. increasing the temperature increases the rate of the reaction
d. both a and b are correct
e. both b and c are correct
____ 35. The presence of a catalyst is thought to increase the rate of a reaction by
a. changing the products that are formed in the reaction
b. decreasing the enthalpy change of the reaction
c. increasing the enthalpy change of the reaction
d. decreasing the activation energy of the reaction
e. increasing the activation energy of the reaction
____ 36. According to the Rate Law, the rate (r) for the reaction must be proportional to
a. [X] d.
b. [Y] e.
c. [products]

____ 40. The following graph represents a reaction of order

a. 0 d. 3
b. 1 e. 4
c. 2
____ 41. The half-life of all radioactive isotopes
a. are all exactly the same
b. are all less than 10 hours
c. vary from milliseconds to billions of years
d. very short
e. cannot be determined

____ 50. The theoretical effect of the chemical nature of the reactants can be explained in terms of collision theory because it affects
I. the collision geometry involved in the reaction
II. the total number of collisions that occur
III. the fraction of collisions that are effective
IV. the required activation energy for a reaction
a. both I and IV d. both III and IV
b. I, II and III are true e. II only
c. both II and III
Short Answer

61. What are the three simplifying assumptions often used in calorimetry?

62. How are nuclear power stations and conventional power stations similar? How are they different?

63. Draw a typical rate of reaction graph (Concentration of Reactant vs. Time) and indicate how to determine an average rate of reaction.

64. Draw a typical rate of reaction graph (Concentration of Reactant vs. Time) and indicate how to determine an instantaneous rate of reaction.

65. Define the term half-life. Give an example.
28.

paraphrase

Question 1:

The power of standard oil can be categorized into three sections based on the already discussed spheres, namely cultural, political and economic. With regards to cultural power, the people ways and habits changed drastically. They were able to access affordable illuminating oil and they no longer had to go to bed with darkness. Economic wise, the other energy sources were quite expensive and the local people were unable to afford. Standard oil made it possible for people to live in better conditions which were suited for their economic status. Political wise, the company was able to avoid government restrictions by recognizing the company as a trust. All these powers had a big role to play in keeping up with the social contract.

Question 2:

The story of standard oil is a clear illustration of the dominance theory. In this approach, the businesses have absolute power and the needs of the general public are not considered. Standard oil had been placed as a trust, and this made the company a monopoly. It resulted into a situation where competition was hindered and new investors could not join the market because it had been protected. This on the other hand was harmful to the consumers who needed competitive firms to come up in their favor. Eventually the business power that had been granted was limited and this gave way to the end of the monopoly.

Question 3:

Considering the stakes at hand at that time, Rockefeller did not act unethically at all. he was the first to come up with the idea of cheap and standard sources of energy, and he had all the rights to protect his innovations. In addition to this, very few people had shown interest at the very start of the business, and people later came to criticize him when the hard labor days had passed and he was not reaping massive profits from his hard work. Being a Christian, he understood the importance of sharing but for a business to succeed one has to come up with an innovation and capitalize on it. His actions were just but mere protection of his ideas and hard work.

Question 4:

The standard oil company was a net plus in establishing ideas that favored the majority in the public. What Rockefeller did was to eliminate the aspect of giving a profit to anyone. He thus came up with many innovations that made this dream possible to achieve. To the advantage of the general public, majority of his products were given at affordable prices, and this made lives of everyone better. At the very beginning, he ensured that people could access cheap power sources, and this idea is what resulted to his magnificent wealth.

Question 5:

At first, the main idea of Rockefeller was to maximizing his profits while helping the general public. With time however, many people had shown interest in the same but Rockefeller was wise enough to have made the company a monopoly and protected its operations. This can be considered unethical because it placed limitation on other people who needed to invest in similar opportunities. He should have made use of better ways of attracting demand, while at the same time giving people the freedom to choose from a wide variety of products. In addition to that, he limited healthy competition , and this had adverse effects on economic growth.