energy calculations and delta h

Question 1

define moles

Answer 1

a unit of measurement for the amount of substance present

Question 2

how many particles in one mole

Answer 2

6.02 x 10^23

Question 3

why do some substances have a heat of combustion of KJ/mol whereas others use KG/g

Answer 3

some substances such as methane and ethane have known chemical formulas, hence the molar mass can be determined to find the moles present. whereas blended fuels such as petrol and biogas do not have exact formulas, hence can only be measured by mass.

Question 4

how to find mole, delta h, energy of substance

Answer 4

delta h = q(KJ)/n(mol) OR q/m(g)

Question 5

density formula

Answer 5

d=m(g)/v(L)

Question 6

define density

Answer 6

how tightly a material is packed closely together, which links its mass to its volume occupied

Question 7

formula for change in enthalpy (KJ/mL)

Answer 7

it provides the amount of energy released or absorbed during a chemical reaction per mL

Question 8

what’s the specific heat capacity of water

Answer 8

4.18J/g/C