AP Biology Quiz 1

About 25 of the 92 natural elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter?

• carbon, sodium, chlorine, nitrogen

• oxygen, hydrogen, calcium, sodium

• carbon, hydrogen, nitrogen, oxygen

• carbon, oxygen, sulfur, calcium

Each element is unique and different from other elements because of the number of protons in the nuclei of its atoms. Which of the following indicates the number of protons in an atom's nucleus?

• atomic mass

• atomic weight

• atomic number

• mass number

Oxygen has an atomic number of 8 and a mass number of 16. Thus, the atomic mass of an oxygen atom is

• exactly 8 grams

• exactly 8 daltons

• approximately 16 grams

• 16 daltons

It might help to draw this out.

Choose all that are true about lithium bonding with chlorine.

• lithium becomes a cation

• one of lithium's electrons goes to chlorine

• this is a covalent bond

• chlorine gains a proton

Which statement is true?

• An atom's atomic mass is the sum of its protons and neutrons.

• An atom's atomic mass is the sum of its protons, neutrons, and electrons.

• All atoms of an element have the same number of subatomic particles.

• Ions of an element have significantly different masses than neutral atoms of an element.

What is FALSE about the elements in group 18?

• Their valence energy levels are full.

• They are inert.

• They have eight electrons in their valence energy levels.

• They are non-reactive.

The book talked about a molecule that has polar covalent bonds. What molecule was it talking about?

• Water

• Hydrongen Gas - H₂

• Oxygen Gas - O₂

• Sodium Chloride NaCl

What element is this?

• Carbon

• Oxygen

• Beryllium

• Seaborgium

When Magnesium bonds with Oxygen, what charge does Magnesium end up with?

• +2

• -2

• It doesn't pick up a charge, it's a covalent bond.

• -1

Which electrons determine the behavior of an atom?

• Valence electrons

• The ones in the inner-most energy level.

• Positive electrons

• Pfluberonic electrons