Question

Please show work: Question below

Answer 1

Answer:

b) 2.0 mol

Explanation:

Given data:

Number of moles of Ca needed = ?

Number of moles of water present = 4.0 mol

Solution:

Chemical equation:

Ca + 2H₂O     →      Ca(OH)₂ + H₂

now we will compare the moles of Ca and H₂O .

                          H₂O        :        Ca                

                             2           :        1

                             4.0           :       1/2×4.0 = 2.0 mol

Thus, 2 moles of Ca are needed.