A student makes three statements about isotopes.
Statement 1: isotopes of an element react in the same way because their atoms have the same electronic configuration
Statement 2: an isotope of an element with more neutrons has a higher atomic number
Statement 3: chlorine has isotopes with mass numbers 35 and 37, so chlorine gas contains Cl2\mathrm{Cl_{2}}Cl2 molecules with three different masses
Which statements are correct?
1 only
1 and 3 only
2 and 3 only
1, 2 and 3
46 exam-style questions on Edexcel GCSE Chemistry 2.1 Atomic structure, covering 2.1.1 Development of the atomic model, 2.1.2 Structure of the atom and subatomic particles, 2.1.3 Mass number, isotopes and relative atomic mass, and 2.1.4 Calculating relative atomic mass from isotopic abundance. Each one has a worked solution and a mark scheme showing where the marks go.