/6 Science Quiz (for 12 to 16 years old): Quiz 8 1 / 6Permanent hardness of water can be removed by adding potassium permanganate chlorine bleaching powder washing soda 2 / 6Marsh gas is nitrogen hydrogen methane ethane 3 / 6The filament of an electric bulb is made of graphite tungsten nichrome iron 4 / 6The two elements that are frequently used for making transistors are iridium and tungsten silicon and germanium boron and aluminium niobium and columbium 5 / 6Diamond is an allotropic form of germanium sulphur carbon silicon 6 / 6In fireworks, the green flame is produced because of mercury sodium potassium barium Your score is 0% Restart quiz Next quiz Please rate the quiz Send feedback By WordPress Quiz plugin