Question

Please help :(

Question 1 (Multiple Choice Worth 2 points)

[06.05]Considering the reaction of the decomposition of N2O5 to form the products NO2 and O2, calculate the average reaction rate if at 0.00s the concentration of N2O5 was 1.00 M and at 4.00s it decreases to 0.987 M?

2 N2O5 4 NO2 + O2

4.97 × 10-1 mol/(L × s)

7.27 × 10-2 mol/(L × s)

6.50 × 10-3 mol/(L × s)

3.25 × 10-3 mol/(L × s)

Question 2 (Multiple Choice Worth 2 points)

[07.06]What is the oxidation number of sulfur (S) in sulfuric acid (H2SO4)?

-6

+2

+4

+6

Answer 1

Question 3 (Multiple Choice Worth 2 points)

[07.02]Which of the following would not neutralize a solution of H2SO4?

sodium hydroxide

nitric acid

lithium hydroxide

ammonia

Question 4 (Multiple Choice Worth 2 points)

[06.04]Which of the following circumstances will result in a reaction that is spontaneous only at high temperatures?

positive enthalpy change and positive entropy change

negative enthalpy change and negative entropy change

positive enthalpy change and negative entropy change

negative enthalpy change and positive entropy change

Question 5 (Multiple Choice Worth 2 points)

[06.03] 15.0g of an unknown substance is heated from 25.0°C to 34.0°C. If 60.6 J of energy is absorbed, identify the unknown substance using the specific heat.



aluminum

iron

silver

lead

Question 6 (Multiple Choice Worth 2 points)

[06.02]When a cold pack is used, ammonium chloride mixes with water and energy is absorbed from the water to reduce the temperature of the water. Which of the following best describes this type of reaction?

endothermic

exothermic

decomposition

synthesis

Question 7 (Multiple Choice Worth 2 points)

[08.05] Which answer provides the correct name for name the following hydrocarbon?



4-ethyl-2-pentyne

4-methyl-2-hexyne

2-heptyne

4-methy-hexane

Question 8 (Multiple Choice Worth 2 points)

[05.07]How many grams of potassium nitrate (KNO3) would form if 2.25 liters of a 1.50 molar lead nitrate Pb(NO3)2 solution reacts with 1.15 liters of a 2.75 molar potassium chromate K2CrO4 solution?

Pb(NO3)2 + K2CrO4 PbCrO4 + 2KNO3

108 g

681 g

639 g

362 g

Question 9 (Multiple Choice Worth 2 points)

[08.03]Which of the following best describes the forces that generate geothermal power?

Heat energy beneath the Earth's surface heats underground water into steam.

Heat from the Earth’s core and pressure transform the remains of dead plants and animals.

Energy of the sun strikes photovoltaic cells producing a flow of electrons.

Heat energy is released during nuclear fission and steam is produced to turn a turbine.

Question 10 (Multiple Choice Worth 2 points)

[06.04]Which of the following reactions results in an increase in entropy?

6CO2 (g) + 6H2O (l) C6H12O6 (s) + 6O2 (g)

N2O4 (g) 2NO2 (g)

H2 (g) + S (s) H2S (g)

2SO2 (g) + O2 (g) 2SO3 (g)

Question 11 (Multiple Choice Worth 2 points)

[05.04]A mixture of two gases exerts a total pressure of 1.22 atm. If the partial pressure of one of the gases is 0.58 atm, what is the partial pressure of the other gas in the mixture?

0.48 atm

0.64 atm

0.71 atm

2.1 atm

Question 12 (Multiple Choice Worth 2 points)

[06.05]According to the collision theory and model created to explain the collision theory, what is the best explanation for why a higher concentration makes a reaction go faster?

There are more collisions per minute.

It increases the distance between the particles.

It increases the average kinetic energy of the particles.

It increases the average kinetic energy and there are more collisions per minute.

Question 13 (Multiple Choice Worth 2 points)

[08.01]Which statement is not correct regarding radiation?

Nuclear reactions arise from an atom’s nucleus.

Alpha, Beta, and Gamma are types of radiation.

Most of the earth’s nuclear energy comes from the Sun.

Radioactive elements have an unbalanced number of protons and electrons.

Question 14 (Multiple Choice Worth 2 points)

[07.05]How would a decrease in volume affect the following reaction?

N2 (g) + O2 (g) 2NO (g)

The equilibrium would shift to the right.

The equilibrium would shift to the left.

There would be no change to equilibrium.

The affect on equilibrium cannot be determined.

Question 15 (Multiple Choice Worth 2 points)

[06.05]Which answer is true regarding this expression and scientific models?

Scientific models must be computer generated to be reliable.

Scientific models are 3D and can be held; expressions are not models.

Scientific models are used only when accurate and expressions are sometimes used.

Scientific models help explain phenomena and can be 2D, 3D, or a mathematical expression.

Question 16 (Multiple Choice Worth 2 points)

[07.03]Which is not true regarding the pH scale?

The neutral pH at 25°C is 7.0.

Bases have a pH greater than 7.0.

The pH scale measures the hydronium ion concentration in solution.

When the concentration of hydroxide ions increases, the pH decreases.

Question 17 (Multiple Choice Worth 2 points)

[06.04]On a potential energy diagram for the following processes, which of the following has a decrease in entropy?

melting

freezing

boiling

sublimation

Question 18 (Multiple Choice Worth 2 points)

[06.05]According to the collision theory and model created to explain the collision theory, why does a catalyst cause a reaction to speed up?

It lowers the activation energy.

It increases the collisions per minute.

It increases the average kinetic energy of the particles.

It increases the kinetic energy and the collisions per minute.

Question 19 (Multiple Choice Worth 2 points)

[06.04]For an exothermic reaction, which of the following conditions must be true for all products?

The change in enthalpy is positive and potential energy diagram is higher.

The change in enthalpy is negative and potential energy diagram is higher.

The change in enthalpy is positive and potential energy diagram is lower.

The change in enthalpy is negative and potential energy diagram is lower.

Question 20 (Multiple Choice Worth 2 points)

[07.05]What would happen to the following endothermic reaction that is in equilibrium if heat is added?

N2O4 (g) 2 NO2 (g)

The reaction would not be affected

The equilibrium would shift to the left

The equilibrium would shift to the right

The product concentration would equal the reactants

Question 21 (Multiple Choice Worth 2 points)

[07.01]Which of the following is not true of bases?

Bases can be electrolytes.

Bases have a distinctly bitter taste.

Bases react with acids to produce a salt and water.

Bases have more hydroxide ions than hydronium ions.

Question 22 (Multiple Choice Worth 2 points)

[08.01]How much of a 0.9500g sample of polonium-218 will remain after 12.16 minutes if the half-life of polonium-218 is 3.040 min?

2.97 x 10-2 g

5.94 x 10-2 g

2.38 x 10-1 g

4.75 x 10-1 g

Question 23 (Multiple Choice Worth 2 points)

[07.01]What happens when an acid reacts with an active metal?

A neutralization reaction occurs.

Hydronium ion concentration is increased.

Oxygen gas is produced.

Hydrogen gas is produced.

Question 24 (Multiple Choice Worth 2 points)

[07.02]If 27.3 mL of 0.293 M HBr solution completely neutralizes 42.6 mL of NH3, what is the concentration of the NH3 solution?

NH3 + HBr NH4Br

0.188 M

0.387 M

0.586 M

2.18 M

Question 25 (Multiple Choice Worth 2 points)

[08.02]Which of the following best describes a chain reaction in a nuclear fission reaction?

The chain reaction continues until the source of power that initiated the reaction is used up or is switched off.

The chain reaction continues until control rods are used to stabilize the uranium-238 which controls the potential for explosions.

The chain reaction continues until the rate of collision between uranium-235 and uranium-238 isotopes falls below useable levels.

The chain reaction continues until all uranium-235 isotopes have split, or until the neutrons fail to collide with any more uranium-235 nuclei.

Question 26 (Multiple Choice Worth 2 points)

[08.02]Which of the following describes nuclear fusion?

It fuels nuclear power plants.

It involves splitting of the nucleus.

It involves the combining of nuclei.

Its chain reactions can be initiated by neutrons.

Question 27 (Multiple Choice Worth 2 points)

[07.06]In the chemical reaction shown below, which element was reduced?

Zn + H2SO4 ZnSO3+ H2O

Zn, because it gained 2 electrons

Zn, because it lost 2 electrons

S, because it gained 2 electrons

S, because it lost 2 electrons

Question 28 (Multiple Choice Worth 2 points)

[05.06]Water is a polar molecule and attracts other polar molecules. Which of the following is a consequence of this property?

Water is considered to be a universal solvent.

Water can only dissolve a limited amount of solute.

When water freezes, the molecules move farther apart.

The water in lakes and ponds freezes from the top down.

Question 29 (Multiple Choice Worth 2 points)

[08.06]Biotechnology seems to cause much controversy. Why is this field more likely to draw attention from the public?

Its processes require a large amount of energy, and the cost makes many upset.

Its results can greatly improve lives, but sometimes the consequences are negative.

It is very poorly understood by the majority of people, yet receives much funding from the government.

It receives funding from private companies who stand to make huge profits at the expense of people who need it.

Question 30 (Multiple Choice Worth 2 points)

[08.05] Which answer provides the correct name for name the following hydrocarbon?



heptane

7-heptyne

7-heptene

2-heptyne

Question 31 (Multiple Choice Worth 2 points)

[06.01]How would a system in which both matter and energy are exchanged freely between the system and the surroundings be classified?

an open system

an isolated system

a closed system

an integrated system

Question 32 (Multiple Choice Worth 2 points)

[07.04]Which answer does not describe the following reaction?

NO (g) + O2 (g) 2 NO2 (g)

The reaction is in dynamic equilibrium.

The reaction does not go to completion.

The reaction is reversible.

The concentration of reactants and products will be equal.

Question 33 (Multiple Choice Worth 2 points)

[07.06]Which element is being oxidized in the redox reaction below?

PbO (s) + NH3 (g) N2 (g) + Pb (s) + H2O (l)

Pb

O

N

H

Question 34 (Multiple Choice Worth 2 points)

[08.01]As people eat foods containing potassium, some of it undergoes beta decay. When this occurs, what element will be the product?

argon

calcium

chlorine

scandium

Question 35 (Multiple Choice Worth 2 points)

[06.03]A 65.0 gram sample of some unknown metal at 100.0° C is added to 204.3 grams of water at 22.0° C. The temperature of the water rises to 27.0° C. If the specific heat capacity of liquid water is 4.18 J/ (°C × g), what is the specific heat of the metal?

0.657 J/ (°C × g).

0.900 J/ (°C × g).

1.11 J/ (°C × g).

2.43 J/ (°C × g).

Question 36 (Multiple Choice Worth 2 points)

[05.08]If 45 g of LiF are dissolved in 1.8 kg of water, what would be the expected change in boiling point? The boiling point constant for water (Kb) is 0.51 °C/m.

0.49°C

0.98°C

1.9°C

3.5°C

Question 37 (Multiple Choice Worth 2 points)

[07.06]Which of the following chemical reactions is an oxidation-reduction reaction?

Fe2O3 + 3CO 2Fe + 3CO2

MgSO4 + 2KI K2SO4 + MgI2

NaNO3 + KCl KNO3 + NaCl

Cu(NO3)2 + 2HBr CuBr2 + 2HNO3

Question 38 (Multiple Choice Worth 2 points)

[06.02]On an exothermic potential energy diagram, what is true for all products?

The products are at the same energy level as the reactants.

The products are at a lower energy level than the reactants.

The products are at a higher energy level than the reactants.

The products do not have energy.

Question 39 (Multiple Choice Worth 2 points)

[05.04]When 7.50 L of sulfur trioxide are produced by the reaction of sulfur dioxide in an excess of oxygen at standard temperature and pressure, how many liters of sulfur dioxide were used?

2SO2 (g) + O2 (g) 2SO3 (g)

3.75 L

5.00 L

7.50 L

15.0 L

Question 40 (Multiple Choice Worth 2 points)

[05.08]Which of the following solutions will have the greatest colligative effect?

2 moles of glucose (C6H12O6) dissolved in 1.0 kg of water (H2O)

1.5 moles of sodium chloride (NaCl) dissolved in 1000.0 kg of water (H2O)

0.75 moles of calcium fluoride (CaF2) dissolved in 500.0 g of water (H2O)

0.50 moles of carbon dioxide (CO2) dissolved in 250.0 g of water (H2O)

Question 41 (Multiple Choice Worth 2 points)

[05.03]A sample of gas has a volume of 2.4 L and a pressure of 1.2 atm. What would the pressure of the same gas sample be if the volume is reduced to 1.8 L at a constant temperature?

0.90 atm

1.6 atm

5.2 atm

3.6 atm

Question 42 (Multiple Choice Worth 2 points)

[06.01]If you drop a 150 gram piece of metal that has a temperature of 125°Celsius into 1000 grams of water at 20°Celsius, what best describes what would occur?

More heat will be lost by the metal than gained by the water.

The temperature of the water will be greater than the amount of heat lost by the metal.

The temperature change of the metal will equal the temperature change of the water.

The heat lost by the metal will equal the heat gained by the water.

Question 43 (Multiple Choice Worth 2 points)

[07.03] What is the pH of a 6.40 × 10-3 M solution of sodium hydroxide, NaOH?

pH = 10.9

pH = 11.8

pH = 12.4

pH = 12.9

Question 44 (Multiple Choice Worth 2 points)

[05.01]Which phase of matter is made up of particles that are packed closely together, with both a definite shape and a definite volume?

gas

liquid

plasma

solid

Question 45 (Multiple Choice Worth 2 points)

[08.05]A carbon atom has a strong tendency to do which of the following?

double bond with electrons

receive electrons

donate electrons

share electrons

Question 46 (Multiple Choice Worth 2 points)

[05.06]When 6.4 grams of LiCl are dissolved in enough water to create a 145-gram solution, what is the solution's concentration, expressed as a percent by mass?

3.2% LiCl

4.4% LiCl

4.6% LiCl

6.4% LiCl

Question 47 (Multiple Choice Worth 2 points)

[08.03]Which of the following natural resources is considered non-renewable?

hydro-electric power

natural gas

solar power

wind power

Question 48 (Multiple Choice Worth 2 points)

[07.06]Which of the following represents the balanced reduction half-reaction from the redox reaction?

Pb + Pd(NO3)2 Pb(NO3)2 + Pd

Pb Pd2+ + e-

Pd2+ + 2e- Pd

Pb + e- Pb

2 Pd2+ + 4 e- 2 Pd

Question 49 (Multiple Choice Worth 2 points)

[05.01]Which of the following describes what occurs as a liquid becomes a solid?

A physical change occurs; the particles of the liquid vibrate faster and their kinetic energy increases.

A physical change occurs; the particles of the liquid vibrate more slowly and their kinetic energy decreases.

A chemical change occurs; the particles of the liquid vibrate faster and their kinetic energy increases.

A chemical change occurs; the particles of the liquid vibrate more slowly and their kinetic energy decreases.

Question 50 (Multiple Choice Worth 2 points)

[08.04]What is the purpose of environmental remediation?

to restore water to its original purity levels

to make the most of currently used technologies and resources

to remove pollution or contamination from the environment

to reuse materials that would otherwise go to waste

Question 51 (Multiple Choice Worth 2 points)

[06.03]What term explains why some materials heat up more quickly than others?

density

mass

specific heat

thermal expansion

Question 52 (Multiple Choice Worth 2 points)

[08.01]Which of the following represents a balanced nuclear equation showing Bismuth-212 undergoing alpha decay followed by beta decay?

+ x- +

+ +


+ +

+ +

Question 53 (Multiple Choice Worth 2 points)

[08.04]Since 1915, chemical fertilizer has been mass produced for farming. Which of the following is the main water pollution problem caused by chemical fertilizer?

increased carbon monoxide

radioactive substances in the water

increased nitrate and phosphate levels

higher levels of bacteria, viruses and protozoa

Question 54 (Multiple Choice Worth 2 points)

[07.04]What is the correct balanced equation for the following equilibrium constant expression?



CO2 (g) CO (g) + ½ O2 (g)

CO2 (g) CO (g) + O2 (g)

2 CO2 (g) 2 CO (g) + O2 (g)

2CO (g) + O2 (g) CO2 (g)

Question 55 (Multiple Choice Worth 2 points)

[05.05]Which of the following would be the best technique to use in order to separate a liquid from a solution?

chromatography

evaporation

filtration

simple distillation

Question 56 (Multiple Choice Worth 2 points)

[06.03]How many joules of heat energy would be needed to raise the temperature of 149.5 grams of water from 25.0° C to 45.0° C? The specific heat capacity of liquid water is 4.18 J/ (°C × g).

31.2 J

713 J

12500 J

15600 J

Question 57 (Multiple Choice Worth 2 points)

[08.05]Which of the following describes a double bond between two carbon atoms?

A double bond will produce four single bonds to form a tetrahedral shape.

A double bond between carbon atoms will eventually form a ring of carbons.

A double bond between carbon atoms is longer than a triple bond between carbon atoms.

A double bond will quickly reduce to single bonds to create three-dimensional tetrahedrals.

Question 58 (Multiple Choice Worth 2 points)

[05.03]If 64 grams of O2 gas occupy a volume of 56 liters at a temperature or 25°C, what is the pressure of the gas, in atmospheres (atm)?

0.073 atm

0.87 atm

1.1 atm

1.7 atm

Answer 2

really taylor, really? -.-