For each question below, there are two statements. Decide whether each statement is true or false. Then decide whether Statement II is a correct explanation for Statement I.
Statement I
Statement II
6. Every aluminum-27 atom has 27 protons BECAUSE The mass number of aluminum-27 is 27.
and 27 electrons.
7. Isotopes of an element have different BECAUSE The nuclei of an element's isotopes contain dif-
atomic masses.
ferent numbers of protons.
8. An electron is repelled by a negatively BECAUSE An electron has a negative charge.
charged particle.
9. In an atom, the number of neutrons is BECAUSE The mass number is generally equal to or
generally equal to or greater than the
greater than the atomic number.
number of protons.