Mole Concept

Question 1

What is avogadro’s constant (not expected knowledge)

Answer 1

6.02214 x 10^23

Question 2

Why is avogadro’s constant important?

Answer 2

It describes how many particles of something there are in one mole of that thing

Question 3

What is molar mass?

Answer 3

It is the mass of an element, that equates to one mole of that element

for example, hydrogen has a molar mass of 1.008 g/mol, so one mole of hydrogen is 1.008 grams of hydrogen.

Hydrogens atomic mass is also 1.008 amu (atomic mass units)

Question 4

If oxygen has an atomic mass of 15.999, what is its molar mass?

Answer 4

15.999 g/mol.

Question 5

What does the equation C=n/v mean

Answer 5

Concentration = moles/litre

Question 6

How can the equation C = n/v be rearranged to find n?

Answer 6

n = C x v

Question 7

What is the empirical formula?

Answer 7

An empirical formula is the simplest ratio of atoms of each element in the compound.
E.g Ba2(NaOH)4 can become Ba(NaOH)2

Question 8

What is the formula to find moles?

Answer 8

Moles = Mass (g)/Molar Mass (g)

Question 9

How to calculate percentage composition

Answer 9

Find total molar mass of chemical, then find molar mass of the individual atom you want to calculate and put it over the total molar mass.