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