Across
- 2. The atoms of halogens are……
- 4. He discovered the electron
- 7. What is the common name for CaCO3
- 9. The series of processes by which nitrogen and its compounds are interconverted in the environment and in living organisms, including nitrogen fixation and decomposition
- 12. Which gas turns limewater milky?
- 13. The time it takes for half of the atoms of a substance to decay
- 17. A radioactive isotope used in the treatment of cancer
- 18. The elements between the groups 2 and 3 are called the
- 20. What are the group seven elements called?
- 21. This process is used to find the age of dead organisms by comparing the amounts of two isotopes of carbon.
- 23. What is the flame colour for potassium
- 24. Plants can create most of the world’s free oxygen through this process
- 26. This element is used to make nuclear power
- 27. This is one of the types of subatomic particle
Down
- 1. The fourth alkali metal
- 3. A type of bonding where electrons are transferred from one atom to another
- 5. What is the seventh element in the periodic table.
- 6. Transition can be hammered into shape without breaking. They are ……
- 8. woman discovered radium?
- 10. A type of bonding where the electrons are shared
- 11. Oxygen and nitrogen can be obtained from liquid air by a process called…
- 14. One of the allotropes of carbon which is used in jewellery
- 15. The emission of energy as electromagnetic waves or moving subatomic particles
- 16. The ore that pure uranium and pure radium can be obtained from.
- 19. Hydrogen burns with a……
- 22. The space an electron occupies is called an
- 25. Elements with the same number or protons and electrons but different numbers of….