Answer: 996 mmHg
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at NTP, weighs equal to the molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
According to the ideal gas equation:
[tex]PV=nRT[/tex]
P = Pressure of the gas = ?
V= Volume of the gas = 25.5 L
T= Temperature of the gas = 13°C = (273+13) K = 286K
R= Gas constant = 0.0821 atmL/K mol
n= moles of gas= 1.42
[tex]P=\frac{nRT}{V}=\frac{1.42\times 0.0821\times 286}{25.5}=1.31atm=996mmHg[/tex] (760mmHg=1atm)
Thus pressure of this gas sample is 996 mm Hg.