Mass of 112 mL of a certain gas is 0.22 g at STP. How many molecules are there in the sample of gas ? What is the molar mass of the gas ?
Answers
Explanation:
Answer:
➜ number of molecules = 30.11 × 10²¹ molecules
➜ molar mass of the gas = 44 g
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Explanation:
\begin{gathered} \\ \\ \end{gathered}
Given,
mass of the given gas, m = 0.22 g
volume of the given gas, V = 112 ml or 0.112 L
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To Find,
☛ number of molecules of the given gas present
☛ molar mass of the gas
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Solution,
\begin{gathered} \\ \end{gathered}
We know,
\begin{gathered} \\ \boxed{ \sf Number \: of \: moles = \frac{volume \: (in \: litres)}{volume \: of \: gas \: at \: S.T.P(22.4)} } \\ \end{gathered}
Numberofmoles=
volumeofgasatS.T.P(22.4)
volume(inlitres)
On substituting the values, we get
\begin{gathered} \\ \\ \sf \rightarrow \quad M = \frac{0.112}{22.4} \\ \\ \sf \rightarrow \quad M = 0.005 \: mol \\ \\ \end{gathered}
→M=
22.4
0.112
→M=0.005mol
Now,
\begin{gathered} \\ \end{gathered}
1 mol = 6.022 × 10²⁴ atoms / molecules
0.005 mol = 6.022 × 0.005 × 10²⁴
➜ 6.022 × 5 × 10²¹
➜ 30.11 × 10²¹ molecules
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Also,
\begin{gathered} \\ \end{gathered}
No. of moles = Mass given / Molar mass
☛ 0.005 = 0.22 / molar mass
☛ molar mass = 0.22 / 0.005
☛ molar mass = 44 g
\begin{gathered} \\ \\ \\ \end{gathered}
Answer:
I hope this will help you
Explanation:
mass of gas = 0.22 g
vol = 112 ml = 0.112 L
so no.of moles = volume in L / volume at STP
= 0.112/22.4 = 0.005 moles
1 mol = 6.022 × 10²⁴ atoms / molecules
0.005 mol = 6.022 × 0.005 × 10²⁴
6.022 × 5 × 10²¹
30.11 × 10²¹ molecules
Also,
No. of moles = Mass given / Molar mass
0.005 = 0.22 / molar mass
molar mass = 0.22 / 0.005
molar mass = 44 g