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WJEC GCSE Science Double Award Substances and atomic structure (Unit 2) overview quiz quiz

14questions. Pick an answer and you'll see why right away.

  1. Which statement best describes a compound?

  2. How many atoms in total are in the formula Ca(OH)2?

  3. Which is the strongest evidence that a chemical reaction has occurred?

  4. What is the correctly balanced equation for hydrogen burning in oxygen?

  5. When magnesium burns in air, why does the mass of the solid increase?

  6. What are the relative charge and relative mass of a neutron?

  7. An atom has a mass number of 27 and an atomic number of 13. How many neutrons does it have?

  8. What defines isotopes of the same element?

  9. What is the electronic structure of a calcium atom (atomic number 20)?

  10. For a main-group element, what does the number of outer-shell electrons tell you?

  11. How does reactivity change down Group 1, the alkali metals?

  12. Why can chlorine displace bromine from potassium bromide solution?

  13. Why are the Group 0 noble gases unreactive?

  14. How would you separate pure water from salt water?