2. Atoms & Elements

Which of the following isotopes has the same number of neutrons as Ca-42?

One isotope of sodium has 11 protons and 7 neutrons. What is the mass number of this isotope?

Which of the following would be an isotope of carbon-14?

How many neutrons are present in the isotope tin-124?

A radioactive nuclide has 53 protons and 78 neutrons. Which is the symbol of this nuclide?

Which isotope of fluorine has 10 neutrons?

Which isotope of cobalt has 32 neutrons?

How many neutrons are present in the isotope manganese-54?

What does the number next to an isotope (for example, carbon-14) signify?

Which of the following isotopes would you expect to be stable?

An isotope of sodium (Na) has a mass number of 22. How many neutrons does it have?

How many neutrons does a lithium (Li) atom typically have?

Bismuth has an atomic number of 83 and its most common isotope has a mass number of 209. How many neutrons are present in this isotope of bismuth?

An atom of the isotope Cs contains how many protons (p)?

Which pair of atoms constitutes a pair of isotopes of the same element?