Question

calaulate the no. of moles and molecules of ammonia gas in a volume 33.6dm3 at STP​

Answer 1

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Given:

Ammonia gas in a volume 33.6 dm3 at STP

To find:

Number of moles and molecules = ?

Solution:

1 dm3 = 1 litre

$\\ \\ Moles = \dfrac{ \: Mass }{molar \: mass} \\ \\ Moles \: = \: \dfrac{volume}{22.4} \\ \\ Moles = \dfrac{Number \: of \: molecules}{6.02 \times 10 {}^{23} }$

Volume = 33.6 dm3 = 33.6 Litre

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$\\ \\ Moles = \dfrac{volume}{22.4} \\ \\ = \dfrac{33.6}{22.4} \\ \\ = 1.5$

$\\ \\ Moles = \dfrac{Number \: of \: molecules}{6.02 \times 10 {}^{23} } \\ \\ 1.5 = \dfrac{Number \: of \: molecules}{6.02 \times 10 {}^{23} } \\ \\ 1.5 \times 6.02 \times 10 {}^{23} = Number \: of \: \\ molecules$

$\\ \\ 9.03 \times 10 {}^{23} = Number \: of \: \\ molecules$

Answer:

Therefore, number of moles is 1.5 and number of molecules is 9.03 × 10^23 in ammonia gas in a volume of 33.6 dm3 at STP

Knowledge booster:

• Learn the formulas mentioned above to solve questions easily
• 1 dm³ = 1 Litre, 1cm³= 10^-3 litre
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