1)
a)
D = 0.79 g/cm³ m = 85.1 g
D = m / V
0.79 = 85.1 / V
V = 85.1 / 0.79 => 107.72 cm³
____________________________________________
b) D = m / V
0.79 = m / 125
m = 0.79 x 125 => 98.75 g
____________________________________________
hope this helps!
Explanation:
Moles of phosphorus pentachloride present initially = 2.5 mol
Moles of phosphorus trichloride at equilibrium = 0.338 mol

Initially
2.5 mol 0 0
At equilibrium:
(2.5 - x) mol x x
So, from above, the moles of phosphorus trichloride at equilibrium , x= 0.338 mol
Mass of 0.338 moles of phosphorus trichloride at equilibrium:
= 0.338 mol × 137.5 g/mol = 46.475 g
Moles of phosphorus pentachloride present at equilibrium :
= (2.5 - 0.338) mol = 2.162 mol
Mass of 2.162 moles of phosphorus pentachloride at equilibrium:
= 2.162 mol × 208.5 g/mol = 450.777 g
Moles of chloride gas present at equilibrium : 0.338 mol
Mass of 0.338 moles of chloride gas at equilibrium:
= 0.338 mol × 71 g/mol = 23.998 g
I think it’s B. I’m not 100% sure but I believe it is B! Srry if this is late btw.
Answer: An inorganic acid.
Explanation: An inorganic acid (also called a mineral acid) is an acid derived from one or more inorganic compounds. All inorganic acids form hydrogen ions and the conjugate base ions when dissolved in water. Commonly used inorganic acids are sulfuric acid (H2SO4), hydrochloric acid (HCl), and nitric acid (HNO3). Hope this helps :)