A1: Amount of substance (Mass)

Question 1

Define mole

Answer 1

The amount of substance that contains 6.02x10^23 particles

Question 2

Avogadro’s constant

Answer 2

6.02x10^23

Question 3

Define molar mass

Answer 3

The mass in grams in each mole of substance, units are gmol^-1

Question 4

Define empirical formula

Answer 4

The simplest whole number ratio of atoms of each element present in a compound

Question 5

Define molecular formula

Answer 5

The actual number of atoms of each element in a molecule

Question 6

Define hydrated salt

Answer 6

Salts with water molecules as a part of their crystalline structure

Question 7

Determining the formula of a hydrated salt experimentally

Answer 7

• weigh an empty crucible
• weigh crucible and hydrated salt
• heat gently for one minute then strongly for 3 more
• leave to cool and then weigh crucible and anhydrous salt
  -calculate ratio of mass of anhydrous salt and mass of water

Question 7

Define anhydrous salt

Answer 7

When a crystalline structure is left without water, and a powder remains

Question 8

RTP gas equation

Answer 8

n=v/24 (in dm^3)

Question 9

Molar Gas volume (Vm)

Answer 9

Volume per mole of gas molecules at a stated temperature and pressure

Question 10

Ideal gas equation

Answer 10

pV=nRT

Question 11

Ideal gas equation units

Answer 11

p=Pa
V=m^3
n=moles
R=8.314J/mol/K
T= K (+273)

Question 12

Assumptions for molecules in an ideal gas

Answer 12

Random motion, elastic collisions, negligible size, no IMFs

Question 13

cm3 to m3

Answer 13

x10^-6

Question 14

dm3 to m3

Answer 14

x10^-3

Question 15

degrees c to K

Answer 15

+273

Question 16

kPa to Pa

Answer 16

x10^3