Answer:
P₂ = 2.88 atm
Explanation:
Given data:
Initial volume of gas = 1.8 L
Final volume = 750 mL
Initial pressure = 17.5 Psi
Final pressure = ?
Solution:
We will convert the units first:
Initial pressure = 17.5 /14.696 = 1.2 atm
Final volume = 750 mL ×1L/1000L = 0.75 L
The given problem will be solved through the Boly's law,
"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"
Mathematical expression:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = initial volume
P₂ = final pressure
V₂ = final volume
Now we will put the values in formula,
P₁V₁ = P₂V₂
1.2 atm × 1.8 L = P₂ ×0.75 L
P₂ = 2.16 atm. L/ 0.75 L
P₂ = 2.88 atm
The mass of hydrated salt - 2.123 g
mass of anhydrous salt - 1.861 g
mass that has been reduced is the mass of water that has been heated and lost from the compound thereby making the salt anhydrous.
therefore mass of water lost - 2.123 - 1.861 = 0.262 g
number of moles of water lost - 0.262 g / 18 g/mol = 0.0146 mol
number of moles of salt - 1.861 g / 380.6 g/mol = 0.00490 mol
molar ratio of moles of water to moles of salt
molar ratio = 0.146 mol / 0.00490 mol = 2.98 rounded off to 3
for every 1 mol of salt there are 3 moles of water
therefore empirical formula - Cu₃(PO₄)₂.3H₂O
