Consider the following statements: Hard water is not suitable for
1) drinking
2) washing clothes with soap
3) use in boilers
4) irrigating crops
Which of these statements are correct?
1 and 3
2 and 3
1, 2 and 4
1, 2, 3 and 4
Correct Answer :
D. 1, 2, 3 and 4
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sucrose
glucose
fructose
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three
four
one
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number of neutrons in the nucleus
number of protons and neutrons in the nucleus
the valency of the element
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Egyptians
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Americans
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Lithium
Helium
Sodium
Cobalt
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Radon
Astatine
Cesium
Ruthenium
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iso-heptane
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atomic mass
number of neutrons
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sodium carbonate
carbonic acid
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red phosphorus
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Hard water does not lather well with soap because
it contains carbonates of calcium and magnesium
it contains sodium chloride
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