Relative Atomic Mass and Isotopes

A series of free IGCSE Chemistry Activities and Experiments (Cambridge IGCSE Chemistry).

Relative Atomic Mass, Isotopes
Describe the term Relative Atomic Mass.
• Mass of an element or atom compared to carbon.

Explain what an isotope is.
• Atoms of a particular element with the same number of protons but different number of neutrons (or different atomic masses)

Calculating Relative Atomic Mass (A_r) for an element.
• The A_r takes into account the mass of each isotopes for each element and their relative abundance.

Exam-style Question:
A sample of boron is made of 20% boron-10 atoms. The rest are boron-11 atoms. Show that the A_r of boron is 10.8.

What are Radioactive isotopes?
Isotopes of an element share chemical properties.
Some isotopes are stable and some are unstable.
Unstable isotopes are radioactive.
Radioactive isotopes are known as radiosisotopes.
Uses of radioactive isotopes
• Find leaks and blockages in underground pipes.
• Medical tracers to provide diagnostic information about the functioning of specific organs in the body

• Show Step-by-step Solutions

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