GK
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Oxygen and carbon
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Hydrogen and oxygen
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Hydrogen and carbon
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None of the above
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Detailed explanation-1: -Water is formed by the chemical combination of hydrogen and oxygen. A molecule of water consists of 2 atoms of hydrogen and 1 atom of oxygen, combined chemically. Figure 1 represents the molecules in liquid water (black – oxygen atom; gray – hydrogen atom).
Detailed explanation-2: -Water consists of one oxygen atom and two hydrogen atoms. This means that the mass of a water molecule is 1g + 1g + 16g = 18 g/ mol.
Detailed explanation-3: -In the electrolysis of water, it is found that the ratio of volumes of hydrogen and oxygen obtained is 2:1 i.e., 2 volumes of hydrogen and 1 volume of oxygen combines to form water.
Detailed explanation-4: -The area around the oxygen is somewhat negative compared to the opposite, hydrogen-containing end of the molecule, which is slightly positive. Opposites attract, so this lopsided charge difference allows bonds to form between the hydrogen and oxygen atoms of adjacent H2O molecules.