Relative Formula Mass

Question 1

What is another way of saying relative atomic mass?

Answer 1

Ar.

Question 2

Relative atomic mass is usually the same as what?

Answer 2

As the mass number of the element.

Question 3

Relative atomic mass is what?

Answer 3

How heavy different atoms are compared with the mass of an atom of carbon-12.

Question 4

Carbon-12 has a relative atomic mass of what?

Answer 4

Exactly 12.

Question 5

Elements in the periodic table all have what?

Answer 5

2 numbers.

Question 6

The smaller number is called what?

Answer 6

Atomic number.

Question 7

What does the atomic number tell us?

Answer 7

How many protons it has.

Question 8

The bigger number is called what?

Answer 8

The mass number.

Relative atomic mass.

Question 9

The relative atomic mass is found where?

Answer 9

The number on top of the element

Question 10

What happens when an element has more than one stable isotope?

Answer 10

The relative atomic mass is an average value of all the different isotopes.

Question 11

How else is relative formula mass written as?

Answer 11

Mr.

Question 12

If an example of a compound which has a relative formula mass?

Answer 12

MgCl2.

Question 13

A compound with a relative formula mass means what has happened?

Answer 13

All the relative atomic masses added together.

Question 14

What would MgCl2 relative atomic mass be?

Answer 14

24 + (35.5 x 2) = 95.

Question 15

Relative formula mass means…

Answer 15

Add up all the relative atomic masses.

Question 16

One mole of a substance is equal to what?

Answer 16

Its Mr, in grams.

Question 17

The relative formula mass of a substance is known as what?

Answer 17

One mole of that substance.

Question 18

What formula do you use to find the number of moles?

Answer 18

Mass in g divided by Mr.

Question 19

How many moles are there in 42g of carbon?

Answer 19

42g divided by 12 = 3.5 moles.