Unit 10 Review

Given the change of phase: CO₂(g) changes to CO₂(s), the entropy of the system

• remains the same

• You cannot determine the answer with the given information.

• increases

• decreases

Which phrase best describe the following reaction 2H₂ + O₂ --> H₂O + energy?

• endothermic, absorbing energy

• endothermic, releasing energy

• exothermic, releasing energy

• exothermic, absorbing energy

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-1

A 0.20 kilogram sample of lead at 120⁰C is put in to a calorimeter containing 0.30 kg of water at 18⁰C. The equilibrium temperature of the mixture is 20.⁰C. Compared to the heat lost by the lead, the heat gained by the water is

• the same

• less

• more

Tags

NGSS.HS-PS3-4

The sequence of steps that occurs in a reaction process is called the

• reaction mechanism.

• order of the reaction.

• rate law.

• overall reaction.

A species that changes the rate of a reaction but is neither consumed nor changed is

• a catalyst.

• an activated complex.

• an intermediate.

• a reaction.

The slowest step in a mechanism is called

• the uncatalyzed reaction.

• the rate - determining step.

• the activation step.

• none of the other answers are correct.

The change in free energy of a chemical equation is represented by a

• △H

• △G

• △T

• △S

100g of 20°C water has 10g of K₂Cr₂O₇ dissolved in it. How much more K₂Cr₂O₇ could dissolve if the solution were heated to 71°C?

• 40g

• 60g

• 50g

• 30g

Tags

NGSS.HS-PS1-5

100g of 50°C water has 25g of K₂Cr₂O₇ dissolved in it. Is this solution saturated, unsaturated, or supersaturated?

• Supersaturated

• Unsaturated

• Saturated

Tags

NGSS.HS-PS3-4

How many grams of Pb(NO₃)₂ can be dissolved in 100g of 34°C water?

• 50g

• 80g

• 70g

• 35g

Tags

NGSS.HS-PS3-4