Chapter 1 - Atomic Structure

Question 1

What is relative atomic mass

Answer 1

It is the mass of an element taking into consideration the mass of all of the isotopes and their abundance compared to carbon-12

Question 2

What is an isotope of an element

Answer 2

An isotope contains the same number of protons but a differing number of neutrons in the nucleus

Question 3

What is a charge?

Answer 3

A charge on an ion is when there is an imbalance between the number of electrons and protons, for example if an electron is lost there is one more proton than the number of electrons, resulting in a positive charge, the reverse is true.

Question 4

How do Time of Flight mass spectrometers work

Answer 4

The sample is bombarded by electrons to knock one off of the sample, forming a + ion which is then accelerated to a constant kinetic energy by an electron field. It is then allowed to accelerate towards a detector plate, where the lowest weight molecules will hit first and form peaks dependent upon their abundance

Question 5

What is the difference between mass number and atomic number?

Answer 5

Mass number is the total number of particles in the nucleus (protons and neutrons) whereas atomic number is only the total number of protonsq

Question 6

What is first ionisation energy? Write an equation for the element M.

Answer 6

First ionisation energy is the amount of energy required to remove one mole of gaseous electrons from one mole of a gaseous substance.
M(g) -> M+(g) + e-

Question 7

What is successive ionisation energies?

Answer 7

Successive ionisation energies is the amount of energy required to remove the NEXT mole of electrons from an already charged ion, and always requires more energy than the previous ionisation energy because there is a greater pull from the nucleus due to fewer electrons being present.