Respuesta :
Answer: 0.024 ml of hydrogen gas are collected at [tex]18.5^0C[/tex] and 755.5mmHg in this single replacement reaction
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} Ba=\frac{85.0g}{137g/mol}=0.620moles[/tex]
To calculate the number of moles for given molarity, we use the equation:
[tex]\text{Molarity of the solution}=\frac{\text{Moles of solute}\times 1000}{\text{Volume of solution in ml}}[/tex]
[tex]3.55M=\frac{\text{Moles of} HCl\times 1000}{275ml}\\\\\text{Moles of }HCl=\frac{3.55\times 275}{1000}=0.976mol[/tex]
The balanced chemical reaction is:
[tex]Ba+2HCl\rightarrow BaCl_2+H_2[/tex]
According to stoichiometry :
2 moles of [tex]HCl[/tex] require = 1 mole of [tex]Ba[/tex]
Thus 0.976 moles of [tex]HCl[/tex] will require=[tex]\frac{1}{2}\times 0.976=0.488moles[/tex] of [tex]Ba[/tex]
Thus [tex]HCl[/tex] is the limiting reagent as it limits the formation of product and [tex]Ba[/tex] is the excess reagent.
As 2 moles of [tex]HCl[/tex] give = 2 moles of [tex]H_2[/tex]
Thus 0.976 moles of [tex]HCl[/tex] give =[tex]\frac{2}{2}\times 0.976=0.976moles[/tex] of [tex]H_2[/tex]
According to ideal gas equation:
[tex]PV=nRT[/tex]
P = pressure of gas = 755.5 mmHg = 0.994 atm (760 mm Hg = 1 atm )
V = Volume of gas in L = ?
n = number of moles = 0.976
R = gas constant =[tex]0.0821Latm/Kmol[/tex]
T =temperature =[tex]18.5^0C=(18.5+273)K=291.5K[/tex]
[tex]V=\frac{nRT}{P}[/tex]
[tex]V=\frac{0.994atm\times 0.0820 L atm/K mol\times 291.5K}{0.994atm}=24.0L=0.024ml[/tex] (1L=1000ml)
Thus 0.024 ml of hydrogen gas are collected at [tex]18.5^0C[/tex] and 755.5mmHg in this single replacement reaction
