Atomic Structure And Isotopes

Question 1

What is the mass number of en element?

Answer 1

The number of protons and neutrons present in the nucleus of the atom

Question 2

What is the atomic number of an element?

Answer 2

The number of protons present in the nucleus of an atom (or electrons present)

Question 3

What are anions/cations?

Answer 3

Anion = negative ion (add to electron number)

Cation = positive ion (subtract from electron number)

Question 4

What is isoelectronic?

Answer 4

Atoms and ions that have the dome number of electrons

Question 5

What is an isotope?

Answer 5

Atoms of the same element with different numbers of neutrons at different masses

Have the same atomic number but different mass number

Question 6

What is relative atomic mass?

Answer 6

The weighted mean mass of an atom of the element compared with 1/12th the mass of carbon 12 (which has a mass of 12)

Question 7

What is relative isotopic mass?

Answer 7

The mass of an isotope compared with 1/12th the mass of carbon-12 (which has a mass of 12)

Question 8

What happens in a mass spectrometer?

Answer 8

Atoms are converted to positive ions and a magnetic field is applied

This deflects the positive ions by different amounts based on mass, so the ions are separated and can then be detected

Question 9

What does the amount of deflections depend on in mass spectrometry?

Answer 9

• size of the particle (heavier = less deflected)
• charge (bigger charge = more deflected)

Question 10

What is a mass spectrum?

Answer 10

A graph showing the relative proportion or abundance of an isotope so the relative atomic mass can be calculated

• abundance/proportion on the y axis
• mass:charge ratio on the x axis