ENERGY: Transformations & Heat

When the hot molecules and the cold molecules mix together the energy of the cold molecules

• increases because they start to move more

• decreases because they stop moving

• stays the same

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5

What happens to the temperature of both substances after they mixed?

• The temperature stayed the same

• The temperature reached equilibrium

• The temperature of both got colder

• The temperature only increased.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5

The temperature of a substance increases as___.

• the substance expands

• the substance's volume increases

• the average kinetic energy of its particles increases

• 
  the substance's mass increases

Answer explanation

The temperature of a substance increases as the average kinetic energy of its particles increases. Higher kinetic energy means particles move faster, resulting in a higher temperature.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

The movement of thermal energy from a warmer object to a cooler object is called:

• heat

• motion

• temperature

• momentum

Answer explanation

The movement of thermal energy from a warmer object to a cooler object is defined as heat. This process occurs naturally, as energy flows from higher to lower temperatures, making 'heat' the correct answer.

Tags

NGSS.MS-PS3-3

Molecules are closest together in a 

• solid

• liquid

• gas

Answer explanation

Molecules are closest together in a solid due to strong intermolecular forces, which keep them tightly packed. In liquids, molecules are still close but can move more freely, while in gases, they are far apart and move independently.

Tags

NGSS.MS-PS1-4

What term describes a liquid changing to a solid?

• deposition

• freezing

• melting

• evaporation

Answer explanation

The term that describes a liquid changing to a solid is 'freezing'. During freezing, the molecules in the liquid lose energy and arrange themselves into a solid structure.

Tags

NGSS.MS-PS1-4

What is the process called when you add more energy to a substance?

• melting

• freezing

• evaporation

• condensation

Answer explanation

The process of adding more energy to a substance typically leads to evaporation, where a liquid turns into a gas. This occurs when molecules gain enough energy to overcome intermolecular forces.

Tags

NGSS.MS-PS1-4

On a cold rainy day a baby is touching a cold window.  It feels so cold. Which way is the heat moving moving? 

• Cold is moving from the window to the hand.

• Heat is moving from the hand to the window.

• Heat doesn't move.

• It moves in currents

Answer explanation

Heat moves from the warmer area (the hand) to the cooler area (the window). Since the baby feels the cold window, it indicates that heat is being transferred from the hand to the window.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-5

Heat transfers from an area of ____temperature to an area of ___ temperature.

• high to low

• low to high

• high to high

• It can travel high to low and low to high. 

Answer explanation

Heat transfers from an area of high temperature to an area of low temperature due to the second law of thermodynamics, which states that energy naturally flows from hot to cold until thermal equilibrium is reached.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

How does this explain how convection works.

• It demonstrates that hot fluids rise and cold ones sink

• It demonstrates that hot fluids sink and cold ones rise

• It demonstrates that they can mix together

Tags

NGSS.MS-ESS2-5

NGSS.MS-ESS2-6