a sample of iron reacted with hydrochloric acid. The liberated hydrogen occupied 40.1mL when colleced over water at 27 degree centigrade ata barometric pressure of 760torr, What is the mall of the sample of iron?
To determine the molar mass of the iron sample, we need to use the ideal gas law equation:
PV = nRT
Where:
P = pressure = 760 torr
V = volume of hydrogen gas = 40.1 mL = 0.0401 L
n = moles of hydrogen gas
R = ideal gas constant = 0.0821 L·atm/(mol·K)
T = temperature = 27°C = 27 + 273 = 300 K
First, let's convert the volume of hydrogen gas to liters:
V = 0.0401 L
Next, let's solve for the number of moles of hydrogen using the ideal gas law equation:
PV = nRT
n = (PV) / (RT)
n = (760 torr * 0.0401 L) / (0.0821 L·atm/(mol·K) * 300 K)
n = 0.03111 mol
Since the balanced equation tells us that 1 mole of iron reacts with 2 moles of hydrochloric acid, the moles of hydrogen gas produced is equal to half the moles of iron reacted.
Therefore, the moles of iron reacted = n / 2
= 0.03111 mol / 2
= 0.01555 mol
The molar mass of iron can be calculated by dividing the mass of the sample by the moles of iron reacted.
Let's assume the iron sample weighs "x" grams.
Molar mass = mass of iron sample (grams) / moles of iron reacted (mol)
Molar mass = x g / 0.01555 mol
Unfortunately, without more information about the sample of iron, we cannot determine the exact molar mass.