Thermochemistry Pre-Assessment

When thermal energy is added to a substance, the substance's particles move:

• More rapidly at an increased diestance from each other.

• More rapidly with less distance between each other.

• More slowly with a greater distance between each other.

• More slowly with a reduced distance between each other.

Tags

NGSS.HS-PS3-2

NGSS.HS-PS3-4

A chemical reaction that absorbs heat from the surroundings is said to be __________ and has a __________ ΔH at constant pressure.

• endothermic; positive

• endothermic; negative

• exothermic; negative

• exothermic; positive

Tags

NGSS.HS-PS1-4

Heat flows from _______ to _______ objects

• cooler to warmer

• warmer to warmer

• warmer to cooler

• cooler to cooler

Tags

NGSS.HS-PS3-4

Heat is measured in 

• joules

• grams

• degrees celcius

the study of energy changes that occur during chemical reactions and changes in state

Tags

NGSS.HS-PS1-4

NGSS.HS-PS1-5

If the enthalpy ter (ΔH) is negative the reaction is ____.

• Endothermic

• Exothermic

• Neutral

Tags

NGSS.HS-PS1-4

A positive ΔH means that:

• In order for the reaction to happen, heat must be input. It is exothermic

• In order for the reaction to happen, heat must be input. It is endothermic.

• When the reaction happens, heat is released. It is exothermic

• When the reaction happens, heat is released. It is endothermic

H₂ + ½ O₂ --> H₂O + 285kJ is an example of a(n)

• Electrical equation

• Heat equation

• Thermochemical equation

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-1

What type of reaction is this?

• Exothermic

• Endothermic

• Kinetic

• Potential

Tags

NGSS.HS-PS1-4

What is true about thermodynamically favorable reactions?

• They need outside energy to be put in

• They always increase entropy

• They always have a negative ΔH

• ΔG is positive