1.2 Amount of substance

Question 1

Define relative atomic mass (Ar)

Answer 1

Mean mass of an atom of an elemetn divided by one twelfth (1/12) of the mean mass of a Carbon-12 isotope

Question 2

Define Relative molecular mass (Mr)

Answer 2

Mean mass of a molecule of a compound, divided by 1/12 of the mean mass of an atom of the carbon-12 isotope

Question 3

What do you call relative molecular mass for ionic compounds

Answer 3

Relative formula mass

Question 4

How many particles are in 1 mole

Answer 4

6.022x10(23)

(Avogadros constant)

Question 5

How to find number of particles

Answer 5

moles x avogadros constant

Question 6

Under standard conditions, what is the trend of pressure in gases

Answer 6

Pressure is proportional to temperature

Question 7

Under standard conditions, what is the trend of Volume in gases

Answer 7

Volume is proportional to temperature

Question 8

Under standard conditions, what is the relationship between volume and pressure

Answer 8

Pressure and volume are inversely proportional

Question 9

What value do you add to celsius to get kelvin

Answer 9

+273

Question 10

Define the empirical formula

Answer 10

Simplest whole number ratio of atoms of each element in a compound

Question 11

Define molecular formula

Answer 11

True number of each atom in the molecule

Question 12

equation for percentage yield

Answer 12

% yield = (actual mass/theoretical mass) x100

Question 13

equation for atom economy

Answer 13

% atom economy = (Mr desired product / Mr total reactnats) x 100

% atom economy = (Mr desired product / Mr total products) x 100

Question 14

What does it mean to have a high atom economy

Answer 14

Little or no waste product, more economically viable, beneficial to environment because less resources used