8 Energetics 1

Question 1

What is enthalpy change?

Answer 1

The overall energy exchanged with the surroundings when a change happens at constant pressure and the final temp is the same as the start temp

Question 2

What is enthalpy measured in?

Answer 2

Kjmol -1

Question 3

What is the symbol for enthalpy change?

Answer 3

Delta H (a triangle with H)

Question 4

What happens when CaO reacts with water?

Answer 4

Exothermic reaction, releasing energy. Delta H is negative as energy is given out to surroundings. The products end at room temperature and pressure.

Question 5

What happens in endothermic reaction?

Answer 5

Energy is being used, delta H is positive. Products end out at higher energy level than reactants.

Question 6

What happens in exothermic reaction?

Answer 6

Energy being released to surroundings, delta H is positive. Products end out at lower energy level compared to reactants.