Cr 5 - Atoms and Nuclear reactions

Question 1

Proton

Answer 1

Positive Charge, Nucleus

Question 2

Neutron

Answer 2

Neutral (no) charge, Nucleus

Question 3

Electron

Answer 3

Negative Charge (electron shells)

Question 4

Isotope

Answer 4

• Isotopes of an element have the same number of protons but different numbers of neutrons.
  i.e. the same Z but different A (Notation)
• Isotopes of an element have the same electron configuration and possess similar chemical properties but have different physical properties

Question 5

Relative Atomic Mass (Ar)

Answer 5

The relative atomic mass found in the periodic table is a weighted average mass of an element.
It depends on the mass of the isotopes and their abundance.
It is based on 1/12 of the mass of an atom of carbon-12
RelativeAtomicMass= ∑(massofisotope×abundance)/total abundance
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Question 6

Mass to charge ratio

Answer 6

The mass-to-charge ratio (m/z) is a key concept in mass spectrometry. It represents the ratio of an ion’s mass (m) to its electric charge (z). Here’s a detailed explanation:
What It Means:
Mass (m):

This is the mass of the ion, usually expressed in atomic mass units (amu or u).
Charge (z):

m/z Ratio:

It combines these two properties into one number:
𝑚/𝑧 =
massofion/chargeofion

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Question 7

Relative abundance

Answer 7

Relative abundance refers to the proportion of a particular isotope of an element compared to all the isotopes of that element in a natural sample. It is usually expressed as a percentage or a fraction.

Question 8

Two types of Nuclear Radiation

Answer 8

Terrestrial from Earth:
- Decay of radioisotopes in natural materials such as rocks, soil, vegetation and ground water.

Cosmic from space.

Question 9

RADIATION

Answer 9

Atoms with unstable combinations of protons and neutrons will undergo a progressive change through a process called Nuclear Decay. Isotopes that do undergo decay are called “Radioisotopes”

Question 10

Where is radiation emitted from and why.

Answer 10

From the nucleus, so that it can achieve stability.

Question 11

Three types of radiation.

Answer 11

Alpha, Beta and Gamma

Question 12

ALPHA (a)

Answer 12

• Same as helium
  {4,2} He 2+ or alpha symbol
• Two protons
• Two neutrons
  Alpha particles penetration: few centimetres through air.
  Alpha particles: 1%-10% the speed of light

Question 13

BETA (B)

Answer 13

• An electron emitted from the nucleus.
  {0, -1} e or B
• A neutron in the nucleus breaks down, releasing a beta particle.
  {1,0} n → {1,1} H + {0, -1}, e
  B particle penetration: Through air, 10-20cm. Stopped by a thin sheet of aluminium foil.
  B particle: 5%-99% speed of light.