What drives chemical reactions

Question 1

Define Standard Enthalpy change of formation

Answer 1

The enthalpy change when one mole of a compound is formed from its elements under standard conditions

can be both

Question 2

Define Standard enthalpy change of combustion

Answer 2

The enthalpy change when one mole of a substance is burnt in excess oxygen under standard condition

Question 3

Why is a polystyrene cup used in calorimeter

Answer 3

because it is a good insulator

Question 4

What is enthalpy change about

Answer 4

(🔺H) the amount of heat energy transferred during a chemical reaction at constant pressure

Question 5

What’s the equation for energy transferred

Answer 5

q= m x c x 🔺T

q (heat transferred J)
m ( the mass of water g )
c specific heat capacity (J
🔺T ( the temperature change) K

Question 6

Calorimetry experiments
name them

Answer 6

• Enthalpy changes of reactions in solutions
• Enthalpy changes of combustion