2.1.1 - Atomic Structure

Question 1

Define relative isotopic mass

Answer 1

The mass of an atom of an isotope compared with 1/12th of the mass of carbon-12

Question 2

Define relative atomic mass

Answer 2

The weighted mean mass of an atom of an element compared with the mass of 1/12th of carbon-12

Question 3

Define relative formula mass

Answer 3

The weighted mean mass of a formula unit compared with 1/12th of carbon-12

Question 4

Define the word isotope

Answer 4

An isotope is an atom of the same element with a different number of neutrons but the same number of protons and electrons.

Question 5

What is the relative mass of a proton?

Answer 5

1

Question 6

What is the relative mass of a neutron?

Answer 6

1

Question 7

What is the relative mass of an electron?

Answer 7

1/1836

Question 8

What is the relative charge of a proton?

Answer 8

+1

Question 9

What is the relative charge of a neutron?

Answer 9

0

Question 10

What is the relative charge of an electron?

Answer 10

-1

Question 11

How is the periodic ordered?

Answer 11

The periodic is ordered by proton number.

Question 12

Do isotopes have a difference in reactivity?

Answer 12

No there isn’t a different in reactivity.

Question 13

Do isotopes have different properties?

Answer 13

Yes they have different melting and boiling points.

Question 14

What is an ion?

Answer 14

Ions are positively or negatively charged atoms created through the loss or gain of electrons.

Question 15

What is the symbol for the mass number (big number)

Answer 15

A

Question 16

What is the symbol for the atomic number (small number)

Answer 16

Z

Question 17

What is the difference between relative molecular mass and formula mass?

Answer 17

Relative molecular mass is used when referring to simple molecules whereas formula mass is used when referring to ionic compounds or giant covalent structures

Question 18

What is the equation to find out the relative atomic mass (Ar) of a known element?

Answer 18

(Abundance x relative mass) + (abundance x relative mass)
———————————————————————————
100

Question 19

What is mass spectrometry?

Answer 19

It is an analytic tool used to find the difference between similar molecules

Question 20

What are the 4 main processes of mass spectrometry?

Answer 20

1. Ionisation
2. Acceleration
3. Deflection
4. Detection

Question 21

What happens in ionisation (mass spec.)?

Answer 21

The sample is vaporised and passed through an ionisation chamber where electrons are emitted to make a positively charged ion (usually +1)

Question 22

What happens in acceleration (mass spec.)?

Answer 22

The ionisation chamber repels the ion causing it to accelerate towards negatively charged slits that decrease in voltage

Question 23

What happens in deflection (mass spec.)?

Answer 23

The ions are deflected by a magnetic field, the lighter mass and the greater the charge the more it is deflected

Question 24

What happens in deflection (mass spec.)?

Answer 24

The ions pass through a mass analyser and are detected on a mass-to-charge ratio