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allsm [11]
4 years ago
10

When was helium discoved?

Chemistry
1 answer:
andrey2020 [161]4 years ago
4 0
It was discovered in 1868.i hope this helps you .
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A substance X contains 10 gram of calcium carbonate calculate the number of mole of calcium carbonate present in X ​
Tasya [4]

\LARGE{ \boxed{  \rm{ \red{Required \: answer}}}}

☃️ Chemical formulae ➝ \sf{CaCO_3}

<h3><u>How to find?</u></h3>

For solving this question, We need to know how to find moles of solution or any substance if a certain weight is given.

\boxed{ \sf{No. \: of \: moles =  \frac{given \: weight}{molecular \: weight} }}

<h3><u>Solution:</u></h3>

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O = 16

❍ Molecular weight of \sf{CaCO_3}

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Then, no. of moles,

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☄ No. of moles of Calcium carbonate in that substance = <u>0.1 moles</u>

<u>━━━━━━━━━━━━━━━━━━━━</u>

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4 years ago
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