Question

q 7. a certain atom has a nucleus containing seven protons and eight neutrons and has seven electrons orbiting the nucleus. this atom is an isotopic form of the element —
options: silicon, nitrogen, chromium, phosphorous

Explanation:

The atomic number of an element is equal to the number of protons in its nucleus. Here, the atom has 7 protons. Nitrogen has an atomic number of 7 (meaning it has 7 protons in its nucleus). Isotopes of an element have the same number of protons (same atomic number) but different numbers of neutrons. So this atom with 7 protons is an isotope of nitrogen. Silicon has atomic number 14, chromium has atomic number 24, and phosphorus has atomic number 15, so they don't match.

Answer:

B. nitrogen (assuming the options are labeled with letters, if not, just "nitrogen" as the correct option)