/6 Science Quiz (for 12 to 16 years old): Quiz 4 1 / 6The average salinity of sea water is 2.5% 2% 3% 3.5% 2 / 6In which of the following activities silicon carbide is used? Making casts for statues Disinfecting water of ponds Making cement and glass cutting very hard substances 3 / 6The group of metals Fe, Co, Ni may best called as main group metals alkali metals transition metals rare metals 4 / 6When an iron nail gets rusted, iron oxide is formed with increase in the weight of the nail without any change in colour or weight of the nail without any change in the weight of the nail with decrease in the weight of the nail 5 / 6Galvanised iron sheets have a coating of chromium zinc tin lead 6 / 6Among the various allotropes of carbon, diamond is the hardest, graphite is the softest coke is the hardest, graphite is the softest diamond is the hardest, coke is the softest diamond is the hardest, lamp black is the softest Your score is 0% Restart quiz Next quiz Please rate the quiz Send feedback