Across
- 3. Plants produce this gas for everyday living.
- 4. In 1912, he discovered the neutron, an electrically neutral particle with a mass similar to that of the proton's.
- 5. The simplest ratio in which the elements of a compound combine with each other to form the compound.
- 9. Atoms of the same element having the same atomic number but consisting of different atomic numbers.
- 10. A region in which there is a high prop-ability of electronic movement.
- 11. This element belongs to group 4 and is located in period 3.
- 12. This gas fills up party ballons.
- 14. It refers to the number of electrons that an atom can accept, donate or share, in order to achieve the structure of the nearest noble gas.
Down
- 1. The number of protons in the nucleus of an atom of an element.
- 2. The mass of one mole is called the .......
- 6. This implies that only one mole of any gas at STP is able to occupy a volume of 22,4dm3.
- 7. This scientist stated that "protons are not evenly distributed throughout the atom, but is concentrated inside the nucleus."
- 8. Its symbol is capital N and small capital A, .
- 13. This gas is used to fill the bright lights, which flashes various colours, in big cities.
- 15. This element makes the the rock which most women love to have on their fingers.