A nucleus with Z Z\,Z protons and N N\,N neutrons undergoes one alpha decay followed by two beta-minus decays. How does the final nucleus compare with the original nucleus?
It has two more protons and six fewer neutrons.
It has the same proton number and four fewer neutrons.
It has four fewer protons and the same neutron number.
It has two fewer protons and two fewer neutrons.
120 exam-style questions on Edexcel GCSE Physics 6.3 Nuclear equations and decay, covering 6.3.1 Beta-minus and beta-plus decay, 6.3.2 Effects of decay on the nucleus, and 6.3.3 Balancing nuclear equations. Each one has a worked solution and a mark scheme showing where the marks go.