Question

In the equation Ca(s) + 2H2O(l) -->Ca(OH)2(aq) + H2(g), list each element used as a reactant, and tell how many atoms of each are needed for this reaction.

Answer 1

See below

Step-by-step explanation:

Ca + 2H2O → Ca(OH)2 + H2

The elements involved are:

• Ca — calcium
• H — hydrogen
• O — oxygen

The numbers of each atom are:

• 1 atom Ca
• 4 atoms H
• 2 atoms O

The 2 in front of H2O multiplies everything in the H2O.