Question

Use the chemical reaction to answer the question.

2H2+O2→2H2O
2
H
2
+
O
2
→
2
H
2
O
There are four atoms of hydrogen (H
H
) before the reaction. How many atoms of hydrogen are present after the reaction?

(1 point)
Responses

8
8

2
2

4
4

5

thx

Answer 1

In the given chemical reaction:

\[ 2H_2 + O_2 \rightarrow 2H_2O \]

Before the reaction, there are 4 atoms of hydrogen, as indicated by the 2 molecules of \( H_2 \) (each containing 2 hydrogen atoms).

After the reaction, the products are \( 2H_2O \). Each water molecule (\( H_2O \)) contains 2 hydrogen atoms, so in 2 molecules of \( H_2O \), there are:

\[ 2 \text{ molecules } \times 2 \text{ H atoms/molecule} = 4 \text{ H atoms} \]

Thus, the number of hydrogen atoms present after the reaction is **4**.

So the correct response is:

**4**