/6 Science Quiz (for 12 to 16 years old): Quiz 17 1 / 6Carbon, diamond and graphite are together called isomorphs allotropes isotopes isomers 2 / 6Chlorophyll is a naturally occurring chelate compound in which central metal is iron copper calcium magnesium 3 / 6Heavy water is PH7 rain water deuterium oxide tritium oxide 4 / 6The gas usually filled in the electric bulb is carbon dioxide hydrogen oxygen nitrogen 5 / 6Washing soda is the common name for Sodium carbonate Calcium carbonate Calcium bicarbonate Sodium bicarbonate 6 / 6Quartz crystals normally used in quartz clocks etc. is chemically silicon dioxide sodium silicate germanium oxide a mixture of germanium oxide and silicon dioxide Your score is 0% Restart quiz Next quiz Please rate the quiz Send feedback By WordPress Quiz plugin