2. Atoms & Elements

Which of the following is the correct nuclear symbol for the isotope of potassium with mass number 40?

Chlorine has two main isotopes: 35^{17}Cl and 37^{17}Cl. Which isotope is the most abundant in nature?

An atom of zinc has an atomic number of 30 and a mass number of 65. How many neutrons does this atom contain? Give your answer to the nearest whole number.

Which of the following pairs are isotopes of each other?

How many neutrons are present in the isotope lithium-7?

Which isotope is commonly used to determine thyroid activity and treat diseases of the thyroid?

In the isotope name carbon-14, what does the number 14 represent?

How many protons are present in an atom of potassium-29?

Which of the following correctly describes the nuclear composition of uranium-235?

Which of the following is the number of neutrons in the most abundant isotope of lead, Pb-208?

Which of the following statements describes an isotope?

What does the number 84 in the name krypton-84 represent?

Which atom has a nucleus that contains 13 protons and 14 neutrons?

Which radioactive isotopes were discovered by Marie and Pierre Curie?

In the isotope polonium-218, what does the number 218 represent?