Warm Up (Enthalpy Stoichiometry)

What does thermochemistry deal with?

• The sound produced by a chemical reaction

• The light emitted by a chemical reaction

• The heat absorbed or produced by a chemical reaction

• The pressure involved in a chemical reaction

Tags

NGSS.HS-PS3-4

Which of the following types of reactions are possible in thermochemistry?

• Exothermic only

• Endothermic only

• Both exothermic and endothermic

• Neither exothermic nor endothermic

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-4

What is an endothermic reaction?

• A chemical reaction that releases heat energy to its surroundings.

• A physical change that absorbs heat from its surroundings.

• A chemical reaction that absorbs heat energy from its surroundings.

• A biological process that generates heat within an organism.

Tags

NGSS.HS-PS1-4

What is an exothermic reaction?

• A reaction that absorbs heat energy from its surroundings.

• A reaction that does not involve any energy change.

• A chemical reaction that releases heat energy to its surroundings.

• A physical change that releases heat energy to its surroundings.

Tags

NGSS.HS-PS1-4

What is the effect of an exothermic reaction on the surroundings?

• It causes the surroundings to become cooler.

• It causes the surroundings to become warmer.

• It has no effect on the temperature of the surroundings.

• It causes the surroundings to become unstable.

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-4

What is enthalpy in chemistry?

• A measure of the total pressure of a system

• A thermodynamic property that represents the total heat energy content of a system

• A type of chemical bond

• A unit of temperature

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-1

How is enthalpy usually measured?

• In pascals (Pa) or atmospheres (atm)

• In moles (mol) or particles

• In joules (J) or kilojoules (kJ)

• In liters (L) or milliliters (mL)

What does ΔH represent?

• The change in pressure during a reaction

• The change in volume during a reaction

• The change in enthalpy during a reaction

• The change in temperature during a reaction