chemical energy

Question 1

Why is it important for chemists to predict whether reactions in an industrial process are exothermic or endothermic

Answer 1

If reactions are exothermic heat will
need to be removed / If reactions are
endothermic heat will need to be
supplied

Question 2

explain the difference between bond enthalpy and mean bond enthalpy

Answer 2

Mean bond enthalpy is an average energy from a number of compounds.
Bond enthalpy relates to only one particular compound

Question 3

what is the formula for calculating density

Answer 3

mass/volume

Question 4

What is enthalpy

Answer 4

a measure of the chemical energy of a substance

Question 5

What is the enthalpy of combustion

Answer 5

enthalpy change when one mole of the substance burns completely in oxygen

Question 6

What is the molar bond enthalpy

Answer 6

the energy required to break one mole of bonds in a diatomic molecule

Question 7

Hydrogen atoms do not show up clearly on an electron density map suggest a reason for this

Answer 7

they only have 1 electron