Question

note: to answer some of the questions, it may help to reference a periodic table
examine the statement.
hydrogen gas and oxygen gas react to produce liquid water.
which equation correctly represents the statement?
○ 2h(g) + o(g) → h₂o(g)
○ h₂(g) + o₂(g) → h₂o(l)
○ 2h₂(g) + o₂(g) → 2h₂o(l)
○ h₂(g) + o(g) → h₂o(l)

Explanation:

Step1: Check the states of reactants and products

Hydrogen gas is \(H_2(g)\), oxygen gas is \(O_2(g)\), and the product is liquid water \(H_2O(l)\).

Step2: Balance the chemical equation

For the reaction \(H_2(g)+O_2(g)\to H_2O(l)\), by using the law of conservation of mass (balancing the number of atoms of each element on both sides).

• For hydrogen atoms: In \(H_2O\) there are 2 H atoms. In \(H_2\), there are 2 H atoms.
• For oxygen atoms: In \(O_2\) there are 2 O atoms. In \(H_2O\) there is 1 O atom. So we multiply \(H_2O\) by 2 to get 2 O atoms on the product side. Then we multiply \(H_2\) by 2 to balance the H atoms. The balanced equation is \(2H_2(g)+O_2(g)\to 2H_2O(l)\)

Answer:

\(2H_2(g)+O_2(g)\to 2H_2O(l)\) (the third option)