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3 years ago

4

A laboratory assistant needs to prepare 35.2 liters of hydrogen at 25.0°C and 101.3 kilopascals. This is the equation for the re

action:
2HCl + Ca → H2 + CaCl2

What volume of 2.3 M hydrochloric acid is required to produce this much gas? Use the ideal gas resource.

A. 0.625 L
B. 0.876 L
C. 1.18 L
D. 1.25 L

(Some chart that I don't understand)

2 answers:

Mars2501 [29]3 years ago

6 0

Answer:

Option A= 0.625 L

Explanation:

Given data:

Volume of hydrogen =35.2 L

Temperature = 25 °C = 25 + 273 = 298 K

Pressure = 101.3 Kpa = 0.99975327 atm

Molarity of HCl = 2.3 mol / L

Volume of HCl require = ?

Solution:

Formula:

PV = nRT

n = PV / RT

n = (0.99975327 atm × 35.27 L) / 0.0821 atm. L/ mol.K × 298 k

n = 35.19 atm . L / 24.4658 L. atm /mol

n = 1.438 mol

we know that molarity is equal to:

Molarity = number of moles / volume in liter

Volume in liter = Number of moles / Molarity

Volume in liter = 1.438 mol / 2.3 mol/ L

Volume in liter = 0.625 L

Ray Of Light [21]3 years ago

6 0

Answer:

D. 1.25

Explanation:

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