chemistry equations

Question 1

equation for relative isotopic mass

Answer 1

isotope 1/ (abundance 1 divided by ab1+ab2) + isotope 2 / (abundance 2 divided by 1ab1+ab2)

Question 2

is the total always 100%

Answer 2

no so make sure u add up ab1 and ab2 etc

Question 3

mass=?

Answer 3

mr X mol

Question 4

how do u find empirical formula

Answer 4

find the ratio of elements as they are (molecular formula) then divide it so it gets to simplest whole number ratio

Question 5

what is avogadros constant

Answer 5

6.02 x 10^23

Question 6

how to find concentration of solute

Answer 6

mass of solute/ total volume of solution

Question 7

how to do water of crystallisation

Answer 7

1) find mr of the product
2)find the ratio of the product to the water remembering mr of water is 18

Question 8

24 moles =?

Answer 8

volume of gas at standard temp and pressure

Question 9

pv=NRT

Answer 9

Pa x m3 = moles x 8.314 x K

Question 10

n=?

Answer 10

vc

Question 11

percentage yield

Answer 11

actual / theoretical x 100

Question 12

atomic economy

Answer 12

mr of useful / all mr

Question 13

what is the calorimitery equation

Answer 13

q=mc delta T

Question 14

what does each letter stand for

Answer 14

q= energy change
m= mass
c= specific heat capacity
delta T= temp change

Question 15

equation for enthalpy

Answer 15

q/1000 n of limiting reactant

Question 16

equation for enthalpy change

Answer 16

total bond enthalpies of reactants - total bond enthalpy of products

Question 17

equation for equilibrium constant Kc

Answer 17

conc of products timsed by each other/ conc of reactants timsed by each other. also each is to the power of their molar ratio

Question 18

how do u find partial pressure

Answer 18

= total pressure times mole fraction.

ie if it was 240Pa and 1/3 then it would be 80Pa

Question 19

how do you find mole fraction (of A)

Answer 19

moles of A / total moles of all gases

Question 20

equilibrium constant Kp

Answer 20

partial pressure of products timsed by each other divided by partial pressure of reactants timsed by each other

Question 21

ARRENHEIUS TO DO

Question 22

rate equation

Answer 22

k = conc of reactants timsed by each other and they are each to the power of their orders

Question 23

what is k

Answer 23

rate constant

Question 24

units of concentration of reaction

Answer 24

moldm-3

Question 25

equation of kc units

Answer 25

moldm-3 timsed by moldm-3 answer of products over reactants

Question 26

equation of kp units

Answer 26

either Pa or kPa or atm timsed by constituent answer of products over reactants

Question 27

rate of reaction equation

Answer 27

change in conc of product or reactant/ time