1 )Explanation:
Dichloride oxide is reacting with water. When we have a non-metal oxide and we combine it with water we produce an acid.
non-metal oxide + water ---> acid
The formula of the oxide that we are given is Cl₂O, the oxidation state of oxygen in oxides is always 2-, so the oxidation state of this +1. To predict the formula of the acid we can combine all the elements and try to cancel them if we can.
The compound produced is HClO, and the hint of the problem says it has only 1 atom of chlorine in it.
Answer: HClO
2) Explanation:
Sodium oxide is reacting with water. When we combine a metal oxide with water we produce an hydroxide. Since the oxide that is reacting is sodium oxide, the product will be sodium hydroxide.
metal oxide + water ---> hydroxide
To predict its formula we have to do something similar to what we did with wthe acid.
Answer: NaOH