The answer is to test a piece of untreated and treated under same conditions!
<span>a pure substance that can be separated into different elements by chemical means</span>
Answer:
(3) NaNO₃
Step-by-step explanation:
Sodium nitrate has ionic bonds, because it consists of Na⁺ and NO₃⁻ ions.
However, the nitrate ions have <em>covalent bonds</em> between the O atoms and the central N atoms.
(1) and (2) are <em>wrong</em>. Both N₂O₅ and HCl consist of nonmetals, so they are <em>covalent</em> compounds.
(4) is <em>wrong</em>. NaCl has <em>only ionic bonds</em> between the Na⁺ and Cl⁻ ions
Answer:

Explanation:
We will need a balanced chemical equation with masses, moles, and molar masses.
1. Gather all the information in one place:
Mᵣ: 18.02
2Na + H₂O ⟶ 2NaOH + H₂
m/g: 72.0
2. Moles of H₂O

3. Moles of Na
The molar ratio is 2 mol Na/1 mol H₂O.
