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1.1 A simple model of the atom, symbols, relative atomic mass, electronic charge and isotopes

1.1 A simple model of the atom, symbols, relative atomic mass, electronic charge and isotopes

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Question 32

A mass spectrometer analysis of a cosmic dust sample returned from an asteroid reveals the abundance of three stable isotopes of magnesium.

The table below shows the mass numbers and their percentage abundances in this cosmic sample:

Isotope Mass NumberPercentage Abundance (%)2468.202515.302616.50\begin{array}{c|c} \text{Isotope Mass Number} & \text{Percentage Abundance (\%)} \\ \hline 24 & 68.20 \\ 25 & 15.30 \\ 26 & 16.50 \\ \end{array}Isotope Mass Number242526​Percentage Abundance (%)68.2015.3016.50​​

Calculate the relative atomic mass (ArA_rAr​) of magnesium in this sample.

Give your answer to 3 significant figures.

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1.1 A simple model of the atom, symbols, relative atomic mass, electronic charge and isotopes Questions

  1. GCSE
  2. /Chemistry
  3. /1.1 A simple model of the atom, symbols, relative atomic mass, electronic charge and isotopes

41 exam-style questions on AQA GCSE Chemistry 1.1 A simple model of the atom, symbols, relative atomic mass, electronic charge and isotopes, covering 1.1.1 Atoms, elements and compounds, 1.1.2 Mixtures, 1.1.3 The development of the model of the atom (common content with physics), 1.1.4 Relative electrical charges of subatomic particles, 1.1.5 Size and mass of atoms, 1.1.6 Relative atomic mass, and 1.1.7 Electronic structure. Each one has a worked solution and a mark scheme showing where the marks go.

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