Which of the following chemical equations is balanced?
a. Zn + HCI —— ZnCl2 + H2
b. 2 Zn + 2 HCI —ZnCl2 + H,
c. 2 Zn + HCI – ZnCl2 + H2
d. Zn + 2 HCI – ZnCl2 + H2

Option d. Zn + 2HCI –> ZnCl2 + H2

Explanation:

First let us generate a balanced equation to know which of the above is balanced.

This is illustrated below:

Zn + HCl —> ZnCl2 + H2

There are 2 atoms of H on the right side and 1 atom on the left side. It can be balance by putting 2 in front of HCl a shown below:

Zn + 2HCl —> ZnCl2 + H2

Now we can see clearly that the equation is balanced as there are equal numbers of atoms of the different elements present on both sides of the equation.

Now let us check for the above equation in the options given in question.

the answer would be a

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