How much water, in grams, can be made from 4.12 × 1024 hydrogen molecules?
1. 195.858
2. 244.898
3. 44.554
4. 159.378
5. 93.8924
6. 170.143
7. 35.2844
8. 123.196
9. 220.677
10. 72.961

Option 8. 123.192g

Explanation:

From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 molecules. Therefore 1mole of H2 contains 6.02x10^23 molecules.

1mole of H2 = 2x1 = 2g

If 1 mole(i.e 2g) of H2 contains 6.02x10^23 molecules,

Then Xg of H2 will contain 4.12 × 10^24 molecules i.e

Xg of H2 =

(2x4.12 × 10^24)/6.02x10^23 = 13.688g.

Now let us generate a balanced equation for the reaction between of Hydrogen to produce water:

2H2+ O2 —> 2H2O

Molar Mass of H2 =2g/mol

Mass of H2 from the balanced equation = 2 x 2 = 4g

Molar Mass of H20 = (2x1) + 16 = 18g/mol

Mass of H2O from the balanced equation = 2 x 18 = 36g.

From the equation,

4g of H2 produced 36g of H2O.

Therefore, 13.688g of H2 will produce = (13.688x36)/4 = 123.192g of H2O

in the given question, the partial pressure is calculated by using the ideal gas equation, that is, pv = nrt

here, p is pressure, v is volume = 25 l, n is number of moles = 0.0104 moles, r is gas constant = -0.0821 l.atm / mol.k

t is temperature = 273 k

p = nrt / v

p = (0.0104 mol × 0.0821 l.atm / mol.k × 273 k) / 25 l

= 0.0093 atm