Amount of Substances (All 3)

Question 1

Moles Equation in terms of mass and mr

Answer 1

Moles = mass/mr

Question 2

% yield equation

Answer 2

Actual / theoretical x 100

Question 3

Concentration equation

Answer 3

Concentration= moles/vol

Question 4

To calculate the average titre you could …

Answer 4

use a larger titre volume
(lower percentage means more reliable result)

Question 5

Ideal Gas equation

Answer 5

PV = nRT

Question 6

conversions Ideal Gas

Answer 6

volume must be in M^3 = cm^3 to M^3 = /1000000
dm^3 to m^3 = /1000
Temp must be in kelvin = C to K = +273
pressure must be in pa = Kpa to Pa = X1000

Question 7

How to calculate empirical formula

Answer 7

Divide the amount of each element by its Ar or Mr
Divide the answers by the smallest value obtained
If there is a decimal, divide by a suitable number to make it into a whole number

Question 8

% atom economy equation

Answer 8

Mr of desired product / sum of Mr reactants x 100

Question 9

To calculate the average titre only…

Answer 9

use concordant results (within 0.1 of each other)

Question 10

Percentage error formula

Answer 10

error of equipment / amount measured x 100