Question

1. in the expression 3 no₂, which number is the coefficient and which number is the subscript? 3 = ____ 2 = ____ 46) in a chemical reaction, a catalyst is something that speeds up the reaction. it is usually written above the arrow in the chemical equation. circle the catalysts in the following reactions: so₂(g) + o₂(g) →v₂o₅ so₃(g) ch₃ch₂oh(aq) + hcl(g) →h₂so₄ ch₃ch₂cl(s) + h₂o(l)

Explanation:

Step1: Recall Coefficient/Subscript Definitions

A coefficient is a number in front of a chemical formula (or formula unit) that indicates the number of molecules/formula units. A subscript is a number within a chemical formula that indicates the number of atoms of an element in a molecule/formula unit.

Step2: Analyze \( 3\text{NO}_2 \)

• For the number \( 3 \): It is in front of \( \text{NO}_2 \), so it is a coefficient (indicating 3 molecules of \( \text{NO}_2 \)).
• For the number \( 2 \): It is within the formula \( \text{NO}_2 \), next to \( \text{O} \), so it is a subscript (indicating 2 oxygen atoms per \( \text{NO}_2 \) molecule).

Answer:

Coefficient: \( 3 \); Subscript: \( 2 \)