Question

A chemical equation is shown:

C2H4 + O2 → CO2 + H2O

According to the law of conservation of mass, how many atoms of oxygen exist in the products of this reaction?

2
4
6
8

Answer 1

c

Explanation:

the answer is 6

Answer 2

Option C is correct.

Atoms of oxygen exist in the products of this reaction is 6.

Explanation:

Given a chemical equation:

`C_2H_4 +O_2 \rightarrow CO_2 + H_2O`

Law of conservation of mass states that it is observed in a balanced chemical equation, which is a chemical equation that shows all mass is conserved throughout the reaction.

To balance the given equation:

First start off by balancing the elements in the complex molecules first and then the single element molecules.

First, we will start with balancing the Carbons.

On the left we have 2 but on the right only 1, so we multiply the
`CO_2` on the right by 2.

Next we look at the Hydrogen.

We have 4 on the left to the given equation, but only 2 on the right.

To balance them;

so, multiply
`H_2O` by 2.

then, equation become;

`C_2H_4 +O_2 \rightarrow 2 CO_2 +2H_2O` .....[1]

Now, looking at the right hand side we have oxygen, 4 from
`CO_2` and 2 from
`H_2O`, then we have total number of oxygen on right hand side is 6.

In order to have 6 on left side we balanced the equation [1] multiply
`O_2` by 3.

then the balanced given equation is:

`C_2H_4 +3O_2 \rightarrow 2 CO_2 + 2H_2O`

Number of oxygen atom exist =
`2 * 2 +2 * 1 = 4 + 2 =6`

Therefore, number of atoms of oxygen exist in the products of this reaction is 6.