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.
Explanation:
The unequal sharing of electrons between the atoms and the unsymmetrical shape of the molecule means that a water molecule has two poles - a positive charge on the hydrogen pole (side) and a negative charge on the oxygen pole (side). We say that the water molecule is electrically polar.
Answer:
Option B.
Explanation:
As any reaction of combustion, the O₂ is a reactant and the products are CO₂ and H₂O. Combustion reaction for ethane is:
2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O
So 2 moles of ethane react with 7 moles of oxygen to make 4 moles of dioxide and 6 moles of water.
Then 2 moles of ethane will produce 4 moles of CO₂
Answer: Sodium bromide is an ionically bonded compound.
(NaBr: Sodium Bromide)