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
of particles.
According to the ideal gas equation:

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
(760mmHg=1atm)
Thus pressure of this gas sample is 996 mm Hg.
It's a mixture of H2O + a soluble substance like, salt.
Answer:
B
Explanation:
the group number is=valence electrons. element 1 is in group 1 element 18 is in group 8. 1<8