PMT Number 1 (Atomic Structure, Isotopes, Compounds, Formulae And Equations

Question 1

Give the definition of the Atomic number

Answer 1

The number of protons in the nucleus of an atom

Question 2

What does the Bohr model add to the atomic models (3)

Answer 2

1) Electrons can only exist in fixed orbits, or shells, and not anywhere in between

2) Each Shell has a fixed energy

3) When an electron moves between shells, electromagnetic radiation is emitted or absorbed. Because the energy of the shells is fixed, the radiation will have a fixed frequency.

Question 3

What is the relative mass of an electron

Answer 3

1/2000

Question 4

Give the definition of an ion

Answer 4

A charged atom or molecule

Question 5

Give the definition of isotopes

Answer 5

Atoms of the same element with the same number of protons and electrons but different numbers of neutrons.

Question 6

Give the definition of mass number

Answer 6

The mean weighted mass of an element in comparison to 1/12th of a carbon 12 atom.

Question 7

What is a mass spectrometer

Answer 7

An instrument which gives accurate information about the relative isotopic mass of a sample and the relative abundance of the isotopes in it.

Question 8

Give the definition of a neutron

Answer 8

A neutral subatomic particle found in the nucleus of an atom. The relative mass of a neutron is 1.

Question 9

Give the definition of relative atomic mass

Answer 9

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

Question 10

What is the definition of relative isotopic mass

Answer 10

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

Question 11

What is an ionic compound

Answer 11

A compound which is made up of oppositely charged ions that are held together by electrostatic forces