enthalpy

Question 1

enthalpy change

Answer 1

reactants-products

Question 2

is enthalpy change of vaporisation endothermic or exothermic

Answer 2

endothermic as energy is required to overcome London forces

Question 3

average bond enthalpy

Answer 3

average enthalpy change when one mole of bonds is broken in gaseous molecules

Question 4

formation

Answer 4

one mole of compound fromed from its elemnts

Question 5

combustijn

Answer 5

one mole of compound competely combusted in o2

Question 6

neutralisation

Answer 6

acid and alkali react to porduce one mole of water

Question 7

Entropy

Answer 7

Measure of disorder in a system

Question 8

Predict how enthalpy changes of hydration of F- and Cl- would differ

Answer 8

Enthalpy of hydration of F- is more negative/exothermic because it has a smaller size
F- has a greater attraction to H2O

Question 9

Is it feasible at all temperatures

Answer 9

🔺G = always negative at all temrpatures

Question 10

Explain why operational conditions used by industry may be different from those required for a maximum equilibrium yield

Answer 10

• high temp to increase rate
• high pressure is expensive to generate
• high/low pressure/temp for maximum yield.
• catalyst increases rate