Lesson 2 - Chemistry of Life Review

Which particles are found in the atomic nucleus?

• protons and electrons

• protons and neutrons

• neutrons and electrons

• protons, neutrons, and electrons

An atom has 3 electrons, 3 protons, and 4 neutrons. The atomic mass is

• 3 daltons

• 6 daltons

• 7 daltons

• 10 daltons

An atom has 4 electrons, 4 protons, and 5 neutrons. The atomic number is

• 4

• 5

• 9

• 13

Each element is defined by its

• number of protons

• number of neutrons

• number of electrons

• number of protons and electrons

Isotopes of the same element differ in their

• atomic number

• number of electrons

• electron shells

• number of neutrons

The first energy shell contains a maximum of

• 1

• 2

• 4

• 8

The valence electron shell is always the

• first

• outermost

• middle

• second

How many electrons would an atom with an atomic number of 9 contain?

• 5

• 9

• 18

• there is not enough information to determine the number of electrons

To achieve a stable state, an atom (other than hydrogen or helium) containing two valence electrons will most likely

• give up the two electrons

• add electrons to fill the valence shell

• share the electrons forming covalent bonds

• do nothing because this is a stable state for most atoms

lons differ from atoms because

• ions contain a different number of neutrons

• ions contain more protons than atoms

• ions have an electrical charge

• ions are not reactive in water