Question

adding up all of the ______ of all of the individual atoms within one molecule of a compound will determine the molecular mass of the compound.

a) atomic masses
b) electrons
c) atomic numbers
d) protons

Explanation:

Analyze the definition of molecular mass

The question asks what must be added together for all individual atoms in a molecule to determine its molecular mass. By definition, the molecular mass of a Chemical Compounds molecule is the sum of the masses of its constituent atoms.

Evaluate the given options

• A) atomic masses: Adding the individual atomic masses of all atoms in a molecule yields the total molecular mass. This is correct.
• B) electrons: Adding the number of electrons gives the total electron count, not the mass.
• C) atomic numbers: Adding the atomic numbers (number of protons) gives the total nuclear charge, not the mass.
• D) protons: Adding the number of protons gives the total proton count, which does not account for neutrons and is not equal to the mass.

Select the correct option

Option A is the only choice that correctly completes the statement to define molecular mass.

Answer:

• A) atomic masses (Correct answer)
• B) electrons
• C) atomic numbers
• D) protons