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) 47) in the last reaction above, which of the compounds are liquids? __ 48) in the last reaction above, which of the compounds are solids? __ 49) in the last reaction above, which of the chemicals are gases? __ 50) in the last reaction above, which of the chemicals are dissolved in water? ____

Explanation:

Step1: Identify Coefficient

In the chemical formula $3\ce{NO2}$, the number written before the chemical formula (the coefficient) indicates the number of molecules. So, 3 is the coefficient.

Step2: Identify Subscript

The subscript is the number written after and below an element symbol, indicating the number of atoms of that element in a molecule. In $\ce{NO2}$, the 2 is the subscript (number of O atoms in each $\ce{NO2}$ molecule).

Answer:

Coefficient: 3; Subscript: 2