Chapter 2 multiple choice review
Compared to a solution of pH 3, a solution of pH 1 is
100 more times acidic
What is the atomic mass of an atom that has 6 protons, 6 neutrons, and 6 electrons?
12
The sodium atom contains 11 electrons, 11 protons, and 12 neutrons. What is the mass number of sodium?
23
Which of the following statements best describes a compound
A compound contains two or more different elements in a fixed ratio
Which of the following statements about pH is true?
An increase in hydrogen ion concentration means a decrease in pH scale units
what is the difference between an ionic bond and a covalent bond?
An ionic bond essentially donates an electron to the other atom participating in the bond, while electrons in a covalent bond are shared equally between the atoms.
The four most common elements in living organisms are
C, H, O, N
Which of the following statements about water is false?
If ice sank, the oceans would eventually freeze solid.
Which of the following statements regarding the oxygen atom of a water molecule is true?
Oxygen attracts electrons less strongly than the hydrogen atoms.
Which of the following statements regarding chemical reactions is false?
Some chemical reactions create electrons; others destroy them.
What happens to an atom if the electrons in the outer shell are altered?
The properties of the atom change
Clots in our blood can lead to a heart attack or stroke by blocking blood flow. If a clot were made up of a mass of proteins, what changed in the proteins to cause them to form the clot?
The proteins were no longer soluble in the blood.
Which of the following is a trace element in the human body?
Zinc
Typically, nitrogen atoms are composed of electrons, protons, and neutrons. An isotope of nitrogen could
be negatively charged. ( it has 7 valence electrons in the outter shell and would need to add one more in order to be "happy" so it would add an electron, making it negative)
Radioactive isotopes
can be used in conjunction with PET scans to diagnose diseases.
The tendency of water molecules to stick together is referred to as
cohesion.
A(n) ________ forms when two atoms share electrons.
covalent bond
A buffer
donates H+ ions when conditions become too basic and accepts H+ ions when conditions become too acidic.
As ice melts
hydrogen bonds are broken
Water molecules stick to other water molecules because
hydrogen bonds form between the hydrogen atoms of one water molecule and the oxygen atoms of other water molecules.
A single water molecule (H—O—H) is held together by
hydrogen bonds.
Water's surface tension and heat storage capacity are accounted for by its
hydrogen bonds.
Which of the following trace elements needed by humans is commonly added to table salt?
iodine
A solution with a pH of 7 is
neutral
A hydrogen atom has one electron. How many covalent bonds can hydrogen form?
one
The hydrogen atoms of a water molecule are bonded to the oxygen atom by ________ bonds, whereas neighboring water molecules are held together by ________ bonds.
polar covalent and hydrogen
Which of the following particles are found in the nucleus of an atom?
protons and neutrons
In the equation 2 H2 + O2 → 2 H2O, the H2 molecules are ________ and the H2O molecules are _______.
reactants; products
Table salt is formed when
sodium donates its single outer electron to chlorine
Which of the following best describes the atomic number of an atom?
the number of protons in the atom
Which of the following is dependent on the ability of water molecules to form hydrogen bonds with other molecules besides water?
the universality of water as a solvent
