Question

Number of moles and number of molecules in 1.4187 L of SO₂ at STP respectively are

• A. 0.1266; \(3.812 \times 10^{22}\)
• B. 0.0633; \(3.812 \times 10^{22}\)
• C. 0.1266; \(7.6238 \times 10^{22}\)
• D. 0.0633; \(7.6238 \times 10^{22}\)

Answer 1

The Correct Option is B

Step 1: Formula used
[4pt] At STP, \(1\) mole of any ideal gas occupies: \[ 22.4\text{ L} \] Number of moles: \[ n=\frac{V}{22.4} \] Number of molecules: \[ N=nN_A \] where \[ N_A=6.022\times10^{23} \] Step 2: Calculate number of moles
[4pt] Given: \[ V=1.4187\text{ L} \] \[ n=\frac{1.4187}{22.4} \] \[ n=0.0633\text{ mol} \] Step 3: Calculate number of molecules
[4pt] \[ N=nN_A \] \[ N=0.0633\times 6.022\times10^{23} \] \[ N=3.812\times10^{22} \] Final Answer: \[ \boxed{0.0633\text{ mol};\; 3.812\times10^{22}\text{ molecules}} \] \[ \boxed{\text{Option (B)}} \]