Answer : The correct option is, 7.58
Explanation : Given,
pOH = 6.42
pH : It is defined as the negative logarithm of the hydrogen ion concentration.
As we know that,

Now put the value of pOH in this expression, we get the pH of this solution.




Therefore, the pH of this solution is, 7.58
Answer:
Volume occupied by Neon gas is 52.67 L
Explanation:
Using Ideal Gas Equation:
PV = nRT
where
P = pressure exerted by the gas = 57 atm
V = volume occupied = ?
n = number of moles = 115 moles
R = Ideal gas constant = 0.0821 L.atm/K.mol
(R value should be taken according to the units of Temperature,pressure, volume and mole)
T = Temperature = 45 + 273 = 318 K
(For temperature conversion from C to K add 273 to temperature:T + 273)
PV = nRT , So
Put values of T,P,n,R
V = 52.67 L
Volume occupied by 115 moles of Neon gas at 57 atm Pressure and 45 C temperature is 52.67 L