Question

Which one of the following statements is false for 0.5mol $C_2{H}_6$? (C=12, H=1 and take Avogadro number =$6\times {10}^{23}$

• A. It is 15 g
• B. It includes molecules
• C. It includes 1mol C atom
• D. It includes 4 atoms

Answer 1

The correct option is D It includes 4 atoms

molar mass of $C_2{H}_6$ =2.(12) + 6.(1)=30g/mol , 1mol $C_2{H}_6$ is 30g/mol 0.5mol $C_2{H}_6$ is=15 g/mol A is true

1mol $C_2{H}_6$ includes $6\times {10}^{23}$
$C_2{H}_6$ molecule, 0.5mol $C_2{H}_6$ includes $C_2{H}_6$ molecules = $3\times {10}^{23}$ $C_2{H}_6$ molecules B is true

1mol $C_2{H}_6$ includes 2mol C atoms 0.5mol $C_2{H}_6$ include?mol C atoms, =1mol C atom, C is true

1mol $C_2{H}_6$ includes $8N_A$ atoms 0.5mol $C_2{H}_6$ includes = $4N_A$ atoms, D is false.