Question

hydrogen gas (h₂) and oxygen gas (o₂) react to form liquid hydrogen peroxide (h₂o₂). which statement is true about the reaction?
○ a. the atoms of the reactants have combined to form a new substance.
○ b. the same atoms are present, so the chemical properties are the same.
○ c. the two gases have mixed together, but a new substance has not formed.
○ d. the product that is formed has the same physical properties as the reactants.

Explanation:

A chemical reaction (H₂ + O₂ → H₂O₂) produces a new substance (hydrogen peroxide) from reactant atoms rearranged into a new structure. Option B is wrong because new substances have different chemical properties. Option C is wrong as mixing is physical, but this is a chemical reaction forming a new substance. Option D is wrong because reactants are gases and the product is liquid (different physical properties).

Answer:

A. The atoms of the reactants have combined to form a new substance.