Final Exam Review - Reaction Energy and Kinetics

Why must chemical equations be balanced?

• The law of creation and destruction

• The law of conservation of energy

• The laws of physics

• The law of conservation of mass

_________________are never lost or gained in a chemical reaction, they are just rearranged.

• atoms

• molecules

• reactants

• products

Which describes an endothermic reaction?

• Spilling bleach on clothing causes the color to change.

• Mixing zinc and hydrochloric acid causes a test tube to turn warm.

• When mixing silicon oil and boric acid, the mixture feels cold.

• Copper is placed in nitric acid and nitrogen dioxide gas is produced.

In an _____________ reaction, the reactants will have more energy than the products. 

• exothermic
• endothermic
• chemical
• activation 

Tags

NGSS.HS-PS1-4

Activation energy is needed during what part of a chemical reaction?

• to end a chemical reaction
• during a chemical reaction
• to start a chemical reation

The specific heat of aluminum is 0.21 J/g°C. How much heat(Q) is released when a 10 g piece of aluminum foil is taken out of the oven and cools from 100° to 50°? Q=cmΔT

• 105 J

• 10.5 J

• 1.05 J

A pot of 2400g of water at a temperature of 25˚C is heated on a stove until the water boils (100˚C). The specific heat of water is 4.18 J/(g˚C).

Determine the heat energy needed to heat the water in the pot to boiling. Q=cmΔT

• 133.76J

• 43,062.2J

• 752,400J

• 1,003,200J

Water has a specific heat of 4184 J/KgºC. Wood has a specific heat of 1760 J/KgºC. What material needs more energy to raise the temperature 1ºC? Q = cmΔT

• Wood

• Water

• Both are the same

A material was cooled from 100ºC to 40ºC. What is the temperature change ΔT?

• 60ºC

• 40ºC

• -60ºC

• -40ºC

How does heat flow?

• Always from cold to warm
• Always from warm to cold
• Both warm to cold & cold to warm
• It depends on the temperature

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4