Enthalpy Changes

The SI unit of heat and energy is the __________.

• calorie
• heat
• joule
• watt

Temperature is a measure of average [blank] energy of individual atoms.

• heat
• potential
• mechanical
• kinetic

Tags

NGSS.HS-PS3-2

ΔH value in an endothermic reaction is a positive number.

• True
• False

Tags

NGSS.HS-PS3-1

 For which of these processes is the value of ΔH expected to be positive?
1.  The temperature increases when calcium chloride dissolves in water.
2.  Steam condenses to liquid water
3.  Water boils
4.  Dry ice sublimates

• 4 only
• 1 only
• 3 and 4 only
• 2 and 3 only

Tags

NGSS.HS-PS3-4

The diagram represents which type of reaction

• endothermic
• exothermic

Tags

NGSS.HS-PS1-4

 _?_  is the amount of energy required to raise the temperature of 1 gram of any substance 1^oC.

• Specific heat
• A calorie
• Thermal energy
• Conduction

Chemical reactions that absorb energy are called

• endothermic
• fast
• slow
• exothermic

Tags

NGSS.HS-PS1-4

Define 'Enthalpy'

• a) Energy stored in the movement of molecules in a substance
• b) The opposite of temperature
• c) The temperature of a molecule
• d) Energy stored in the chemical bonds in a substance

Tags

NGSS.HS-PS1-4

What would be the effect on the particles if more heat is supplied to the system?

• They would slow down
• They would stop moving
• They would speed up
• There would be no effect

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

What is a tool that measures the heat of chemical reactions?

• calorimeter
•  calorie
• Styrofoam™ cup
• none of these

Tags

NGSS.HS-PS3-4