Amount of substance

Question 1

define one mole

Answer 1

the amount of substance in grams that has the same number of particles as there are atoms in 12 grams of carbon12

Question 2

define molar mass

Answer 2

the mass in grams of 1 mol of a substance given in gmol-1

Question 3

equation linking mass, mole and molar mass

Answer 3

n= m/Mr

Question 4

equation linking molar mass, volume of gas and molar gas volume

Answer 4

n x molar gas volume = volume

Question 5

define molecular formula

Answer 5

the actual number of atoms of each element in a compound

Question 6

define empirical formula

Answer 6

the simplist ratio of atoms of each element in a compound

Question 7

what is a hydrated/ hydrous salt

Answer 7

a salt molecule loosely attached to water called water of crystallisation

Question 8

what is a solute

Answer 8

what is being dissolved in a solvent

Question 9

what is a solvent

Answer 9

the liquid in which a solute dissolved in to form a solution

Question 10

what does 1 litre equal to

Answer 10

1dm3

Question 11

what is the ideal gas equation

Answer 11

pv=nrt

Question 12

what is the conversion between kelvin and celsius

Answer 12

add 273 to C to get K

Question 13

equation linking mole concentration and volume

Answer 13

n=cv

Question 14

what is a limiting reagent

Answer 14

a reactant that runs out first and limits how much product is formed

Question 15

give 4 reasons as to why percentage yield is below 100%

Answer 15

reaction may not of had enough time to complete
a side reaction
product was lost under purification
reversible reactions

Question 16

give 3 reasons why high atom economy is good

Answer 16

environmental friendly
economical
sustainable

Question 17

give two ways ti increase atom economy

Answer 17

use an alternative reaction pathway with a higher atom economy e.g by using an element with lower Mr
find a use for the waste product

Question 18

equation linking avagadros constant and moles

Answer 18

no of particles = n x avagadros constant