Topic 3- Quantitive Chemistry

Question 1

What does mr mean?

Answer 1

Relative molecular mass

Question 2

what is a solvent?

Answer 2

Any substance that substances dissolve in

Question 3

what is a solute?

Answer 3

any substance that dissolves into a solvent

Question 4

what is a solution?

Answer 4

a solution consists of a solvent with a solute dissolved in it

Question 5

how to calculate Mr

Answer 5

1
Identify the Ar of each element
2
Multiply the Ar by the number of atoms
3
Add up the totals for each element

Question 6

CONSERVATION OF MASS STATES

Answer 6

mass of reactants=mass of products

atoms cannot be created or destroyed in a reaction the total mass of the reaction stays the same

Question 7

what is the difference between molecular and imperial formula?

Answer 7

The molecular formula shows the actual amount of atoms which make up a molecule. The empirical formula shows the simplest ratio of atoms which make up a molecule.

Question 8

what does a molecular formula show?

Answer 8

The molecular formula shows the actual amount of atoms that make up a molecule .e.g. glucose is C6H12O6
where as in empirical formula glucose is
CH2O

Question 9

what is the equation for calculating the number of moles?

Answer 9

number of moles=mass/number of 1 mole(mr or ar)
Number of moles= mol
M= Mr =g
m= mass= g

Question 10

calculating atom economy

Answer 10

Mr of desired product from equation/sum of Mr of all reactants from equation X100

Question 11

Percentage yield equation

Answer 11

Percentage yield=Actual Yields/theoretical yield X100

Question 12

Percentage yield equation

Answer 12

Percentage yield=Actual Yields/theoretical yield X100

Question 13

what is relative atomic mass(Ar)

Answer 13

The average mass of all the isotopes of that element

Question 14

What is a chemical change?

Answer 14

A rearrangement of the atoms in the reactants, to form the products