calculations

Question 1

moles

Answer 1

mass/mr

Question 2

PV

Answer 2

nRT

Question 3

R value

Answer 3

8.31

Question 4

concentration

Answer 4

moles/volume

Question 5

degrees to celcius

Answer 5

add 273

Question 6

cm3 to dm3

Answer 6

/1000

Question 7

cm3 to m3

Answer 7

/1000000

Question 8

dm3 to m3

Answer 8

/1000

Question 9

avogadros constant

Answer 9

6.022 x 10(23)

Question 10

number or particles

Answer 10

moles of substance x avogadro

Question 11

density

Answer 11

mass/volume

Question 12

empirical formulae method

Answer 12

1) divide each mass by atomic mass
2) divide each step 1 answer by smallest step 1 answer
3) multiply step2 to give whole numbers

Question 13

mass concentration unit

Answer 13

gdm-3

Question 14

nee diluted concentration

Answer 14

original conc x (original vol/ nee diluted vol)

Question 15

percentage yield

Answer 15

actual yield/ theoretical yield x 100

Question 16

percentage atom economy

Answer 16

mass of used products/ mass of all reactants x 100

Question 17

time of flight

Answer 17

d x square root of (mass/2KE

Question 18

KE

Answer 18

1/2 mass x volume squared

Question 19

relative atomic mass

Answer 19

isotonic mass off each x % abundance/ 100

or

isotopic mass of each x relative abundance/ total relative abundance

Question 20

molar mass

Answer 20

mass/number of moles

Question 21

concentration of solution

Answer 21

number of moles of solute/ volume of solution

Question 22

kc

Answer 22

products/reactants

Question 23

ICE

Answer 23

initial value
change
equilibrium

Question 24

energy change in calorimetry method

Answer 24

mass of solution x heat capacity(Jg-1K-1) x temp change

Question 25

enthalpy change of reaction method

Answer 25

1) energy change
2) moles of reactants
3) divide energy change by moles of reactant not in excess to give delta H
4) add sign and unit

Question 26

delta h reaction of formation

Answer 26

products-reactants

Question 27

delta h of reaction for combustion

Answer 27

reactants - products

Question 28

delta h in general

Answer 28

bond energies broken - bond energies made