Zinc will react with hydrochloric acid to produce hydrogen gas. zn(s)+2hcl(aq)⟶zncl2(aq)+h2(g)what is the volume of h2 gas produced if 2.00g of zinc is used with an excess of hydrochloric acid in the reaction above at stp? round to 3 significant figures.

0.690 liters is the volume of hydrogen gas produced if 2.00 grams of zinc is used with an excess of hydrochloric acid.

Explanation:

Mole so zinc =

According to reaction, 1 mole of zinc gives 1 mole of hydrogen gas.

Then 0.03077  mole of zinc will give :

of hydrogen gas

Pressure of hydrogen gas ,P= 1 atm

Temperature  of of hydrogen gas ,T= 273.15 K

Volume of hydrogen gas = V = ?

Moles of hydrogen gas = 0.03077 mol

PV = nRT (Ideal gas equation )

V = 0.690 L

0.690 liters is the volume of hydrogen gas produced if 2.00 grams of zinc is used with an excess of hydrochloric acid.

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%

i'm pretty sure its b i might be wrong though!