7.3 Energy Changes in Reactions

Energy changes in chemical reactions are determined by changes that occur in chemical bonding.

• True

• False

Tags

NGSS.HS-PS1-4

____ is the energy stored in the chemical bonds of a substance.

• Entropy

• Heat energy

• Chemical energy

• Kinetic energy

Tags

NGSS.HS-PS1-4

____ is a measure of the average kinetic energy of the particles in a sample of matter.

• Bond energy

• Temperature

• State of matter

• Mass

Tags

NGSS.HS-PS3-2

The amount of energy needed to raise the temperature of one gram of a substance one degree Celsius is the _____.

• Degree unit

• Joule

• Specific heat

• Heat unit

In a chemical reaction the heat that is released or absorbed is measured with a _____.

• calorimeter

• furnace

• cup

• timer

Tags

NGSS.HS-PS1-4

A chemical reaction that releases energy to its surroundings is called a(n) ____.

• spontaneous

• endothermic

• exothermic

• entropy

Tags

NGSS.HS-PS1-4

A chemical reaction that absorbs energy from its surroundings is called a(n) _____.

• spontaneous

• endothermic

• exothermic

• entropy

Tags

NGSS.HS-PS1-4

The measure of the disorder or randomness of a system is called entropy.

Determine whether entropy is increasing or decreasing in the following:

H₂O_(g) → H₂O_(s)

• Increasing entropy

• Decreasing entropy

The measure of the disorder or randomness of a system is called entropy.

Determine whether entropy is increasing or decreasing in the following:

2N₂O_5(g) → 4NO_2(g) + O_2(g)

• Increasing entropy

• Decreasing entropy

The measure of the disorder or randomness of a system is called entropy.

Determine whether entropy is increasing or decreasing in the following:

Na⁺_(aq) + Cl^-_(aq) → NaCl_(s)

• Increasing entropy

• Decreasing entropy