1.2 Amounts Of Substance (part 1)

Question 1

Relative atomic mass

Answer 1

Weighted average mass of all the isotopes relative to 1/12th mass of an atom of carbon-12

Question 2

Relative molecular mass

Answer 2

Mass of a molecule of the compound relative to 1/12th of the mass of an atom of carbon-12

Question 3

Relative formula mass

Answer 3

Mass of one formula unit of an ionic compound relative to 1/12th mass of an atom of carbon-12

Question 4

Mole

Answer 4

Amount of substance that contains as many particles as there are in exactly 12g of carbon-12

Question 5

Avogadros constant

Answer 5

6. 02x10 (to the power) 23

or. There are 6.02x10 (to the power) 23 atoms of carbon in 12g carbon-12

Question 6

Does a mole of one substance contain the same number of particles as a mole of any other substance

Answer 6

Yes

Question 7

What do you need to know to calculate moles in a solid

Answer 7

Mass

Question 8

What do you need to calculate the number of moles in a gas

Answer 8

Volume

Question 9

What do you need to know to calculate the number of moles in a solution

Answer 9

Volume and concentration

Question 10

How do you get from Mg to mg

Answer 10

/1000

Question 11

How to you get from mg to g

Answer 11

/1000

Question 12

How do you get from Mg to g

Answer 12

/1000000

Question 13

How to get from g to kg

Answer 13

/1000

Question 14

How to get from kg to tonnes

Answer 14

/1000

Question 15

How to get from g to tonnes

Answer 15

/1000000

Question 16

How to get from tonnes to kg

Answer 16

X1000

Question 17

How to get from kg to g

Answer 17

X1000

Question 18

How to get from tonnes to g

Answer 18

X1000000

Question 19

How to get from g to mg

Answer 19

X1000

Question 20

How to get from mg to Mg

Answer 20

X1000

Question 21

How to get from g to Mg

Answer 21

X1000000

Question 22

Formula for calculating moles in solids

Answer 22

Mass (in g) = moles x Mr

Question 23

How to calculate the number of atoms in a gives mass

Answer 23

First calculate number of moles using mass/Mr

Then calculate number of atoms using moles x avogadros constant

Question 24

How to get from centimetres cubed to decimetres cubed

Answer 24

/1000

Question 25

How to get from decimetres cubed to centimetres cubed

Answer 25

X 1000

Question 26

What do you need to know in order to calculate the number of moles in a solution

Answer 26

Volume in demimetres cubed | Concentration in moles per decimetres cubed

Question 27

What is concentration

Answer 27

The number of moles of a solute dissolved in one decimetre cubed of solution

Question 28

What is the formula to work out the number of moles in a solution

Answer 28

Moles = volume x concentration

Question 29

How to calculate the concentration of a solution given the mass and volume

Answer 29

``` Moles= mass/Mr Concentration= moles/volume in decimetres cubed ```

Question 30

What are the assumptions made when using the ideal gas equation to

Answer 30

* there are no intermolecular forces between the molecules | * the volume occupied by the molecules is entirely negligible relative to the volume of the container

Question 31

What is the ideal gas equation

Answer 31

pV = nRT

Question 32

What unit is the answer always given in

Answer 32

Metres cubed

Question 33

What is pressure measured in

Answer 33

Pascals, Pa

Question 34

How to get from kPa to Pa

Answer 34

X 1000

Question 35

How to get from MPa to Pa

Answer 35

X1000000

Question 36

What is volume measured in

Answer 36

Metres cubed

Question 37

How to get from centimetres cubed to metres cubed

Answer 37

/1000000

Question 38

How to get from decimetres cubed to metres cubed

Answer 38

/1000

Question 39

What is n

Answer 39

Number of moles

Question 40

What is R

Answer 40

Gas constant: 8.314

Question 41

What is T measured in

Answer 41

Kelvin, K

Question 42

How to get from Celsius to kelvin

Answer 42

+ 273

Question 43

How to get from kelvin to Celsius

Answer 43

-273

Question 44

What is density

Answer 44

It's mass per unit volume

Question 45

Formula for density

Answer 45

Mass = density x volume

Question 46

What is density usually measured in

Answer 46

Grams per centimetre cubed

Question 47

Empirical formula

Answer 47

Simplest whole number ratio of atoms of each element present in a molecule

Question 48

Molecular formula

Answer 48

Actual number of atoms of each element present in a molecule

Question 49

How to calculate molecular formula

Answer 49

Calculate empirical formula Calculate relative mass of empirical formula Use Mr to calculate how many times bigger molecular formula needs to be compared to empirical Times number of atoms by how many times bigger mr is than empirical formula mass