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Atoms & Basic Chemistry
Types of Chemical Bonds
The Properties of Water
Carbon Macromolecules
Enzymes & Reactions
100
Atoms are composed of a. protons b. neutrons c. electrons d. all of the above
all of the above - protons, neutrons, and electrons
100
Ionic bonds form between molecules that have a. opposite charges. b. the same charge. c. no charges. d. neutral charges.
opposite charges.
100
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.
polar molecule
100
Which of the following is NOT an organic macromolecule? a. carbohydrate b. ice c. lipid d. nucleic acid
ice
100
An enzyme a. is not used up when catalyzing a reaction. b. lowers the activation energy of a reaction. c. bonds with a substrate molecule at the enzyme's active site. d. all of the above.
all of the above
200
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.
occupy the space surrounding the nucleus.
200
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.
covalent bond
200
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.
water is polar and oil is nonpolar
200
All organic compounds contain the element a. carbon. b. nitrogen. c. calcium. d. sodium.
carbon
200
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.
are biological catalysts
300
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.
carbon atom.
300
Weak attractions between polar molecules are ______________ bonds.
hydrogen
300
Acidic solutions have a pH that is a. less than 7. b. between 7 and 14. c. a negative number. d. more than 7.
less than 7
300
Which of the following organic molecules are classified as carbohydrates? a. amino acids b. fatty acids c. nucleotides d. sugars
sugars
300
The starting materials for chemical reactions are called _________________, while the new substances that are formed are called _______________.
reactants; products
400
A substance that is composed of only one type of atom is called a(n) a. nucleus. b. cell. c. element. d. molecule.
element.
400
The attraction that causes water to bond together to form drops is __________________.
cohesion
400

Due to the polarity of water, compounds that dissolve best in water contain a. nonpolar covalent bonds. b. ionic bonds. c. polar covalent bonds. d. both b and c.

both ionic bonds and polar covalent bonds

400

Long chains of monosaccharides are called _________ .

polysaccharides

400
The energy needed to start a chemical reaction is called ______________ ___________.
activation energy
500

A _______________ is a group of atoms held together by covalent bonds.

molecule

500
The portion of an enzyme molecule into which a specific substrate bonds is called the __________ _______.
active site
500
Water heats and cools more ____________ than other liquids.
slowly
500
Lipids are _______________ molecules because they have no negative and positive poles.
nonpolar
500
The molecule on which an enzyme acts is called the ________________.
substrate