GK
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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carbon
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water
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oxygen
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iron
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Detailed explanation-1: -Hydrogen, oxygen and nitrogen are elements as each of them are made up of two identical atoms. Whereas water is made up of two hydrogen atoms and one oxygen atom, therefore it is not an element.
Detailed explanation-2: -Water is a compound because it is made up of water molecules. There is no such thing as water atoms. Water molecules are made of hydrogen and oxygen atoms, in the definite proportion of two hydrogens for one oxygen.
Detailed explanation-3: -Silica is not an element rather it is a compound that is composed of silicon and oxygen atoms. The chemical formula of silica is .
Detailed explanation-4: -The elements which form water are Hydrogen and Oxygen.
Detailed explanation-5: -First Element: Earth More commonly known as sand, silica is a major component of glass.