Answer: 78.54 grams
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to its molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the number of moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]
[tex]\text{Number of molesof} NO=\frac{29.5g}{30.01g/mol}=0.98moles[/tex]
[tex]2NO+Br_2\rightarrow 2NOBr[/tex]
According to stoichiometry :
2 moles of [tex]NO[/tex] react with 1 mole of [tex]Br_2[/tex]
0.98 moles of [tex]NO[/tex] react with =[tex]\frac{1}{2}\times 0.98=0.49[/tex] moles of [tex]Br_2[/tex]
Mass of [tex]Br_2=moles\times {\text{Molar mass}=0.49\times 159.8=78.54g[/tex]
Thus 78.54 g of [tex]Br_2[/tex] are required to react completely with 29.5 g of NO.
