Question

question 7 of 10
what does percent composition tell you about a molecule?

a. it gives you the total number of atoms in the molecule.

b. it tells you the ratio of elements in the molecular formula.

c. it tells you how the elements are arranged in the molecule.

d. it tells you how much of a molecule is made up of each element.

Explanation:

• Option A: Percent composition doesn't give the total number of atoms; that's related to molecular formula or structure count, not percentage by mass/amount of elements.
• Option B: The ratio of elements in the molecular formula is about the subscripts (stoichiometric ratio), while percent composition is the percentage of each element in the compound by mass (or other relevant measure), not the same as the formula's element ratio directly.
• Option C: How elements are arranged (molecular structure/geometry) is determined by bonding and structural analysis, not percent composition.
• Option D: Percent composition is defined as the percentage (by mass, or sometimes by moles) of each element in a compound. So it tells how much of a molecule (compound) is made up of each element.

Answer:

D. It tells you how much of a molecule is made up of each element.