Question

10 multiple choice 1 point
what is the purpose of an arrow in a chemical equation?
○ to separate the individual chemical species
○ to provide information about the states of matter
○ to denote the direction of the chemical reaction
○ to separate the coefficients and chemical symbols
clear my selection
11 multiple choice 1 point
given this chemical equation, what state of matter is methane, ch₄?
ch₄(g) + 2o₂(g) → co₂(g) + 2h₂o(i)
○ aqueous
○ liquid
○ solid
○ gas
clear my selection

Explanation:

Question 10

• Analyze each option:
• "to separate the individual chemical species" is done by plus signs, not arrows.
• "to provide information about the states of matter" is done by subscripts like (s), (l), (g), (aq), not arrows.
• "to denote the direction of the chemical reaction" is the correct purpose of the arrow in a chemical equation (reactants → products).
• "to separate the coefficients and chemical symbols" is not the role of the arrow.

In the chemical equation \( CH_4(g) + 2O_2(g)
ightarrow CO_2(g) + 2H_2O(l) \), the subscript in parentheses next to \( CH_4 \) is (g), which stands for gas. So methane (\( CH_4 \)) is in the gas state.

Answer:

C. to denote the direction of the chemical reaction

Question 11