Thermochemistry

Question 1

Joule (J)

Answer 1

1J = 1 kg m²/s²

Question 2

Calorie

Answer 2

Amt of energy needed to raise 1 g of H2O 1°C

1 Cal = 4.184J

Question 3

Specific Heat (Capacity), s

Answer 3

Amt of heat needed to raise the temp of 1g of substance by 1°C

J/g°C or cal/g°C

s = q/m∆T
- q, heat
- m, mass
- T, temp

Question 4

Molar heat capacity

Answer 4

The amount of heat needed to raise 1 mole of substance 1°C, S = J/mol°C or cal/mole°C

Question 5

Enthalpy change, ∆H

Answer 5

The heat lost or gained by a system during a rxn at constant pressure

∆H < 0 = exothermic
∆H > 0 = endothermic

Question 6

Calculating standard heat of reaction

Answer 6

Sum of all products - sum of all reactants, f = formation reaction (from a table)

∆H_rxn= ɛ∆H_f(products)-ɛ∆H_f(reactants)