Exam 3: Chemistry of Life

Explain the role of buffers in maintaining the proper environment in which the body can function.

As the hydrogen ion concentration increases, the pH value increases.

The number and arrangement of electrons orbiting in an atom's outer shell determine its chemical activity.

The atomic number of an atom determines its identity.

For sodium to transform from a neutral atom to a positive ion, it must:

A neutral atom that has 22 protons must have 22 electrons.

A negatively charged subatomic particle that moves around the nucleus is a(n):

The chemical reaction of an acid with a base will produce a salt and water.

Because oxygen has eight electrons, it has achieved its octet and will not react with other elements.

Radioactivity can cause an atom of one element to change to that of another element.

A substance that resists changes in pH when acids or bases are added is called a buffer.

Describe the Bohr model of the atom.

Hydrogen will react with other atoms to get eight electrons in its outer energy level.

A neutral atom that has 22 protons must have 22 neutrons.

The type of chemical reaction most likely to require energy is a(n) _____ reaction.

The "coat" of water that forms around charged solutes is often called a(n):

Releases a hydroxide ion into solution, which raises the pH

The mass of a proton is almost exactly equal to the mass of an electron.

A magnesium atom has an atomic number of 12, an atomic mass of 25, and a +2 charge. This atom would contain _____ protons, _____ neutrons, and _____ electrons.

The "aliveness" of a living organism depends on the mixture of elements of which it is made.