Question

There are 4.67 * 10 ^ 24 hydrogen gas molecules the react with 21.0 Liters of oxygen gas STP conditions to form water. How many grams of water will form? How many moles of the excess reactant will remain after the reaction is completed?

Answer 1

I am almost done

Step-by-step explanation:

21.0 L

↓

2H₂(g) + O₂(g) → 2H₂O(l)

↑

4.67 × 10²⁴ moles

[This is done so the equation is balanced and the reaction can occur]

[subscripts are the number of atoms, and the coefficients are the number of molecules]

______________

Since there are about 6.02 × 10²³ moles in one mol of a substance.

4.67 × 10²⁴ / 6.02 × 10²³ =

7.7547174437 mol.

Next, we must determine the grams per mole of each substance, this can be done with the periodic table.

Since hydrogen, and oxygen gas are diatomic, they will consist of two atoms each. So the atomic mass will be multiplied by 2 to get the molecular mass. Therefore H₂ will have a molecular mass of 1.00794 × 2 = 2.01588 g/mol.