Thermodynamics Progress Check

Kinetic energy is measured as

• Activation energy

• Mass

• Temperature

• Potential energy

Answer explanation

Temperature is a measure of kinetic energy.

Tags

NGSS.HS-PS3-2

NGSS.HS-PS2-1

Describe the movement of molecules at a low temperature

• They are moving quickly

• They are moving slowly

• They are vibrating in place

• Molecules don’t move, only atoms do

Answer explanation

Tags

NGSS.HS-PS3-4

Convert 55 C to Kelvin

• -228 K

• 28 K

• 218 K

• 328 K

Answer explanation

To go from celsius to Kelvin, add 273

Convert 55 K to C

• -218

• 0.28

• 328

• 128.5

Answer explanation

To go from Kelvin to celsius, subtract 273

When does all atomic and molecular motion stop?

• 0 F

• 0 C

• Relative zero

• Absolute zero

Answer explanation

A chemical reaction takes relatively low energy molecules and turns them into higher energy molecules. Is this process endothermic or exothermic?

• Endothermic

• Exothermic

Answer explanation

The reaction went from low energy to high energy. That means it had to absorb energy from its surroundings and it must be endothermic.

Tags

NGSS.HS-PS1-4

A chemical reactions takes relatively high energy molecules and turns them into lower energy molecules. Is this process endothermic or exothermic?

• Endothermic

• Exothermic

Answer explanation

The reaction starts high energy and goes to low energy. It must have given off its energy to the surroundings. It is exothermic.

Tags

NGSS.HS-PS1-4

Does this diagram to the left show an endothermic or an exothermic reaction?

• Endothermic

• Exothermic

Answer explanation

The reaction started with low energy and ended with higher energy. Energy went into the reaction. It must be endothermic.

Tags

NGSS.HS-PS1-4

Does this diagram to the right show an endothermic or an exothermic reaction?

• Endothermic

• Exothermic

Answer explanation

This reaction started with high energy and ended with low energy. Energy must have gone out of the reaction. It is exothermic.

Tags

NGSS.HS-PS1-4

Is fire endothermic or exothermic?

• Endothermic – the reaction absorbs energy so the room gets hotter

• Endothermic – the reaction absorbs energy so the room gets colder

• Exothermic – the reaction releases energy so the room gets hotter

• Exothermic – the reaction releases energy so the room gets colder

Answer explanation

The room gets hotter. That energy must have come from the firs, which is giving off heat. So fire is exothermic. You start with high energy fuel and end with low energy smoke and ashes.

Tags

NGSS.HS-PS1-4