Atomic Structure

Question 1

What is relative atomic mass?

Answer 1

The “weighted mean” mass of an atom relative to 1/12th of the mass of a carbon-12 atom

Question 2

What is isotopic mass?

Answer 2

The mass of an atom of an isotope relative to 1/12th of the mass of a carbon-12 atom

Question 3

How do you calculate the relative atomic mass of two isotopes?

Answer 3

Multiply the atomic mass by the percentage

Divide by the two percentages added together (they must add to give 100)

Question 4

Why are neutrons present in the nucleus?

Answer 4

Provide binding so that the protons don’t repel each other

Question 5

What is the charge and mass of a proton?

Answer 5

+1

1

Question 6

What is the charge and mass of a neutron?

Answer 6

0

1

Question 7

What is the charge and mass of a electron?

Answer 7

-1

1/1836

Question 8

What are isotopes?

Answer 8

Atoms of the same element but with a different number of neutrons but same number of protons

Question 9

What are the 3 isotopes of hydrogen?

Answer 9

Protium
deuterium
Tritium

Question 10

What is the formula for ammonium?

Answer 10

NH4 +

Question 11

What is the formula for nitrate?

Answer 11

NO3 -

Question 12

What is the formula for sulfate?

Answer 12

SO4 2-

Question 13

What is the formula for hydroxide?

Answer 13

OH -

Question 14

What is the formula for phosphate?

Answer 14

PO4 3-

Question 15

What is the formula for carbonate?

Answer 15

CO3 2-

Question 16

What is the formula for permanganate?

Answer 16

MnO4 -

Question 17

What is the formula for dichromate?

Answer 17

Cr2O7 2-

Question 18

What is the formula for chromate?

Answer 18

CrO4 2-

Question 19

What is the formula for peroxide?

Answer 19

O2 -

Question 20

When writing ionic equations what do you do?

Answer 20

Write out the ionic equation
Eliminate spectator ions
Don’t include giant structures eg. solids or covalent bonds

Question 21

Why did Niels Bohr think Rutherford’s model was wrong?

Answer 21

Electrons couldn’t be freely orbiting as if this was true they would spiral into the nucleus
So he said they were in a fixed orbital/shell

Question 22

According to Bohr, what happens when electrons in an atom move from one shell to another?

Answer 22

Electromagnetic radiation is emitted or absorbed

Question 23

How do you know if something is polar?

Answer 23

If it has all the same elements attached + lone pair
Or
If it hasn’t got al the same elements + no lone pair

Question 24

How do you know if something is non-polar?

Answer 24

If something hasn’t got all the same elements + lone pair
Or
If it has all the same elements + no lone pair