Atoms & Basic Chemistry
Atoms are composed of
a. protons
b. neutrons
c. electrons
d. all of the above
d. all of the above - protons, neutrons, and electrons
Ionic bonds form between molecules that have
a. opposite charges.
b. the same charge.
c. no charges.
d. neutral charges.
a. opposite charges.
A molecule, like water, that has a partial positive charge on one side and a partial negative charge on the other side is called
a. nonpolar molecule.
b. polar molecule.
c. charged molecule.
d. bipolar molecule.
b. polar molecule
Which of the following is NOT an organic macromolecule?
a. carbohydrate
b. nucleus
c. lipid
d. protein
b. nucleus
The portion of an enzyme molecule into which a specific substrate bonds is called the __________ _______.
active site
The electrons of an atom
a. are found in the nucleus along with the protons.
b. occupy the space surrounding the nucleus.
c. have a positive charge.
d. are attached to the positive charge of neutrons.
b. occupy the space surrounding the nucleus.
The bond formed when two atoms share a pair of electrons is called a(n)
a. hydrogen bond.
b. ionic bond.
c. covalent bond.
d. water bond.
c. covalent bond
When placed in the same container, oil and water do not mix because
a. they are both polar.
b. water is polar and oil is nonpolar.
c. they are both nonpolar.
d. water is nonpolar and oil is polar.
b. water is polar and oil is nonpolar
All organic compounds contain the element
a. carbon.
b. nitrogen.
c. calcium.
d. sodium.
a. carbon
Enzymes
a. are able to heat up molecules so that they can react.
b. always provide carbon dioxide for chemical reactions.
c. are biological catalysts.
d. absorb excess heat so that reactions occur at low temperatures.
c. are biological catalysts
The smallest particle of matter that can retain the chemical properties of carbon is a(n)
a. carbon molecule.
b. carbon macromolecule.
c. carbon atom.
d. element.
c. carbon atom.
Weak attractions between polar molecules are ______________ bonds.
hydrogen
Acidic solutions have a pH that is
less than 7
Which of the following organic molecules are monomers of carbohydrates?
a. amino acids
b. glycerol fatty acids
c. nucleotides
d. simple sugars
d. simple sugars
The starting materials for chemical reactions are called _________________, while the new substances that are formed are called _______________.
reactants; products
A substance that is composed of only one type of atom is called a(n)
a. nucleus.
b. cell.
c. element.
d. molecule.
c. element.
The attraction that causes water to bond together to form drops is __________________.
cohesion
Due to the polarity of water, compounds that dissolve in water contain
a. nonpolar bonds.
b. ionic bonds.
c. polar bonds.
d. both b and c.
d. both ionic bonds and polar bonds
A(n) _______________ is a group of atoms held together by covalent bonds.
molecule
If a fatty acid chain has 1 (one) or more double bonds in it, the molecule is called a(n) ______________ fat.
unsaturated
Water heats and cools more ____________ than other liquids.
slowly
Lipids are made up of what 2 monomers?
glycerol and fatty acids