Use the chemical reaction to answer the question.
2H2+O2→2H2O
There are four atoms of hydrogen (H
) before the reaction. How many atoms of hydrogen are present after the reaction?
(1 point)
Responses
2
2
8
8
4
4
5
The correct answer is: 4.
Which is most likely to occur during a chemical reaction?(1 point)
Responses
Mass is conserved.
Mass is conserved.
The original substance maintains its properties.
The original substance maintains its properties.
New atoms are created.
New atoms are created.
Atoms of the original substance are lost.
The correct answer is: Mass is conserved.
Why?
Mass is conserved during a chemical reaction because atoms cannot be created or destroyed. They can only rearrange to form new substances. Thus, the total mass of the reactants before the reaction should be equal to the total mass of the products after the reaction.
The chemical equation given is 2H2 + O2 -> 2H2O. This means that 2 molecules of hydrogen react with 1 molecule of oxygen to produce 2 molecules of water.
In each molecule of hydrogen (H2), there are 2 atoms of hydrogen. Therefore, if there are four molecules of hydrogen before the reaction, the total number of atoms of hydrogen is 4 molecules x 2 atoms/molecule = 8 atoms.
So, the correct answer is 8.
To answer this question, we need to understand the concept of balancing chemical equations.
In the given chemical equation, 2H2 + O2 → 2H2O, it states that two molecules of hydrogen gas (H2) react with one molecule of oxygen gas (O2) to produce two molecules of water (H2O).
Since each molecule of hydrogen gas (H2) contains 2 hydrogen atoms, if we have 2 molecules of hydrogen gas, then the total number of hydrogen atoms would be 2 x 2 = 4.
Therefore, after the reaction, there are 4 atoms of hydrogen present.
So the correct answer is 4.