2. Atoms & Elements

What is the mass number of a typical helium atom?

A dalton is a unit used to express which of the following quantities?

Element M has two naturally occurring isotopes: M-24 (abundance: 78.99%, mass: 23.985 amu) and M-25 (abundance: 21.01%, mass: 24.986 amu). What is the average atomic mass (in amu) of element M?

On another planet, the isotopes of titanium have the given natural abundances.

Lithium has two naturally occurring isotopes: lithium-6 (mass = 6.015 u, abundance = 4%) and lithium-7 (mass = 7.016 u, abundance = 96%). What is the average atomic mass of lithium?

What is the mass number of the most abundant isotope of the element copper (Cu)?

Which of the following is closest to the atomic mass of argon (Ar)?

Which of the following is the atomic mass of potassium (K)?

An atom has 16 neutrons and 16 protons. What is its approximate atomic mass?

Which of the following elements has the largest atomic mass?

What does it mean if the atomic mass of an element is 10.8?

Which numerical setup can be used to determine the atomic mass of bromine, given its two naturally occurring isotopes, Br-79 (abundance: 50.69%, mass: 78.918 amu) and Br-81 (abundance: 49.31%, mass: 80.916 amu)?

What is the mass number of sodium?

A naturally occurring sample of an element contains only two isotopes. The first isotope has a mass of 68.9255 amu and a natural abundance of 60.11%. The second isotope has a mass of 70.9247 amu. Determine the atomic mass of the element.

Calculate the atomic mass of element X given its isotopes X-45 with a mass of 44.8776 amu and 32.88% abundance, and X-47 with a mass of 46.9443 amu and 67.12% abundance.