Hydrogen has three isotopes. Heavy water is made from one of these isotopes, called deuterium.
The table shows information about some particles.
| Particle | Atomic number | Mass number | Charge |
|---|---|---|---|
| hydrogen-1 atom | 1 | 1 | 0 |
| deuterium (hydrogen-2) atom | 1 | 2 | 0 |
| tritium (hydrogen-3) atom | 1 | 3 | 0 |
| ion X | 1 | 2 | 1+ |
| helium-3 atom | 2 | 3 | 0 |
How many neutrons are in a tritium atom?
State the number of protons, neutrons and electrons in ion X.
Two students make statements about hydrogen-1 and deuterium.
Student A: "Hydrogen-1 and deuterium are different elements, because they have different mass numbers."
Student B: "Deuterium atoms react in the same way as hydrogen-1 atoms, because they have the same number of electrons."
Evaluate the students' statements.
Heavy water has the formula D2O\mathrm{D_{2}O}D2O, where D is a deuterium atom.
Calculate the percentage increase in relative formula mass from H2O\mathrm{H_{2}O}H2O to D2O\mathrm{D_{2}O}D2O.
Relative masses: H = 1.0, D = 2.0, O = 16.0
101 exam-style questions on OCR GCSE Chemistry 1.2 Atomic structure, covering 1.2.1 Development of the atomic model, 1.2.2 The nuclear model and the size of atoms, and 1.2.3 Subatomic particles in atoms and ions. Each one has a worked solution and a mark scheme showing where the marks go.