Chemistry 1: Parts of an Atom

An ion of aluminum has a charge of 3+. The ion contains 10 electrons. How many protons does a neutral atom of aluminum process?

13

Fluoride-19 has an atomic number of 9 and a mass number of 19. How many neutrons does an atom of fluoride-10 contain?

10

The atomic mass and abundance of Si-28 is 27.977 amu and 92.2%. The atomic mass and abundance of Si-29 is 28.976 amu and 4.7%. The atomic mass and abundance of Si-30 is 29.974 amu and 3.1%. Which is the average atomic mass of silicon?

28.09 amu

The four natural isotopes of iron have atomic masses of 53.9, 55.9, 56.9, and 57.9. If these were the only isotopes of iron and they occurred in equal abundance, which would be closest to the atomic mass of iron?

56

An atom of uranium, whose atomic number is 92, transforms in nature to an atom of thorium plus a nucleus of helium, whose atomic number is 2. What is the atomic number of thorium?

90

Isotope A contains 56 protons and 80 neutrons. Isotope B contains 55 protons and 81 neutrons. Isotope C contains 57 protons and 80 neutrons. Isotope D contains 56 protons and 74 neutrons. Which isotopes have the same mass number?

A and B

A particle contains 12 protons, 12 neutrons, and 10 electrons. What is the identity of the particle?

A magnesium ion

The atomic number of polonium is 84. The atomic number of lead is 82. Which must occur for polonium to be transformed into lead.

An atom of polonium, must lose two protons.

Which atom has the greatest mass?

An atom with 8 protons, 8 neutrons, and 8 electrons

An atom of an element loses one proton and one electron. Which statement describes the result of this event?

A neutral atom of a new element is formed.

Which particle is a neutron most equal to in mass?

A proton

A sulfur atom contains 16 protons and 16 electrons. What must occur for this sulfur atom to become a sulfur ion with a charge of 2-?

It must gain two electrons.

Which qualities describe the mass and charge of an electron?

Mass 1/1836 that of a proton; negative charge.

Cadmium has eight naturally occurring isotopes. What do the isotopes have in common?

Number of protons

An atom of carbon-14 contains six protons, eight neutrons, and six electrons. Which will an atom of carbon-12 contain?

Six protons, six neutrons, and six electrons