Question

PLEASE HELP! DUE TODAY! How many gram of magnesium react with 120 ml H3PO4 (with molar concentration 2M)?​

Answer 1

3.89 g Mg

Step-by-step explanation:

2M = 2 mol/L

120 mL = 0.120 L

2 mol/L *0.120 L = 0.240 mol H3PO4

3Mg + 2H3PO4 ----> Mg3(PO4)2 + 3H2

from reaction 3 mol 2 mol

given 0.240mol x mol

x = 0.240*2/3 = 0.16 mol Mg

M(Mg) = 24.3 g/mol

24.3 g/mol *0.16 mol = 3.89 g Mg