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