Question

What mass of zinc will completely react with 18.9 L of oxygen gas at 15°C and 1.50 atm pressure to produce zinc oxide. Remember to write a balanced. equation and fill in what is needed to answer this question on the BCA table.

Answer 1

Answer:

Mass of zinc react with oxygen = 156.91 g

Explanation:

Given data:

Volume of oxygen = 18.9 L

Temperature = 15°C

Pressure = 1.50 atm

Mass of zinc react with oxygen = ?

Solution:

Chemical equation:

2Zn + O₂     →       2ZnO

Number of moles of oxygen:

PV = nRT

1.50atm ×18.9 L = n× 0.0821 atm.L / mol.K × 288 K

28.35 atm.L =  n× 23.64atm.L / mol

n = 28.35 atm.L  / 23.64atm.L / mol

n = 1.2 mol

Now we will compare the moles of oxygen and Zn.

             O₂          :           Zn

               1            :            2

              1.2          :        2/1×1.2 = 2.4 mol

Mass of zinc required:

Mass = number of moles × molar mass

Mass = 2.4 mol × 65.38 g/mol

Mass = 156.91 g