Question

Which of the following statements is MOST accurate regarding atoms?

Most atoms cannot combine with other atoms
Atoms of the same element may have
different mass numbers
Atoms only contain protons
Chemical reactions divide atoms into
smaller units

Answer 1

Atoms of the same element may have different mass numbers. Chemical reactions do not divide atoms into smaller units.

Step-by-step explanation:

Atoms of the same element may have different mass numbers. For example, chlorine has two isotopes with mass numbers 35 and 37. This means that atoms of the same element can have slightly different masses due to the presence of different numbers of neutrons. However, atoms of the same element still have the same number of protons, which determines the element's identity.

In chemical reactions, atoms are combined, separated, or rearranged. This is how chemical compounds are formed, as atoms of different elements can combine in simple whole number ratios. Chemical reactions do not divide atoms into smaller units, but rather rearrange them to form new substances.

Answer 2

Atoms of the same element may have different mass numbers.

Step-by-step explanation:

Mass number is the number of protons + the number of neutrons in an atom. Atoms of the same element can have different number of protons, and hence different mass numbers.

Atoms of the same element with different numbers of protons (but same numbers of neutrons) are called isotopes.

Hope this helps!