Enthalpy and Thermochemistry

The SI unit of heat and energy is the __________.

• calorie
• heat
• joule
• watt

Tags

NGSS.HS-PS3-4

ΔH value in an endothermic reaction is a positive number.

• True
• False

A catalyst works by

• changing the order of the reaction
• increasing the temperature
• lowering the activation energy
• making the activated complex

What type of reaction is shown in the reaction pathway?

• endothermic reaction
• exothermic reaction

Tags

NGSS.HS-PS1-4

How do you calculate Enthalpy of a reaction?

• ΔH = ΔH_products - ΔH_reactants

• ΔT = q / mC

• ΔG = ΔH -TΔS

• E = mc²

Which statement is true regarding endothermic reactions?

• a) Temperature change is positive and enthalpy change is positive
• b) Temperature change is positive and enthalpy change is negative
• c) Temperature change is negative and enthalpy change is positive
• d) Temperature change is negative and enthalpy change is negative

Tags

NGSS.HS-PS1-4

Endothermic reactions feel

• warm
• cold

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

NGSS.HS-PS3-1

A reaction that gives out energy to the surroundings causes the surroundings ....

• temperature to drop

• temperature to rise

• temperature to remain constant

• temperature to vary

Tags

NGSS.HS-PS1-4

The enthalpy change is a negative (-) value, what side of the equation will the energy value be on.

• Reactants

• Products

Tags

NGSS.HS-PS1-4