Question

Please show work:
Question below

Answer 1

b) 2.0 mol

Step-by-step 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.