Electrons move about the nucleus of an atom in regions called ___________________.
Electron cloud, energy level, or energy shell
100
Two atoms that share electrons are held together by ____________________ bonds
Covalent Bonds
100
Which property is responsible for the fact that water and oil do not mix? a. density b. mass c. phase d. polarity
d. polarity
100
What are the basic building blocks of proteins?
Amino Acids
100
Carbon compounds that come from living organisms are called __________________ compounds.
organic
200
Boron's has 5 protons. How many neutrons does Boron-12 have?
7
200
If a neutral atom contains 18 protons, how many electrons does it have?
18 electrons
200
A hydrogen bond can form between a hydrogen atom of one molecule and which atom of another molecule? a. carbon b. hydrogen c. oxygen d. sodium
c. oxygen
200
What are the smaller building blocks that make up nucleic acids?
Nucleotides
200
When added to water, how does an acid affect the pH?
Decreases the pH
300
Atoms of two or more elements chemically combined are termed ____________________.
compounds
300
Balance the following equation: __N2O4 -----> __NO2
N2O4 -----> 2NO2
300
The substance in a solution that dissolves the outher substance.
Solvent
300
Glycogen, used to store energy in theliver and muscle tissue, is an example of which type of molecule? a. protein b. carbohydrate c. saturated fatty acid d. steroid
b. carb
300
A(n) _________________ increases the rate of a reaction by lowering the activation energy.
enzyme
400
Carbon 12 and Carbon 14 have the same number of protons but different numbers of neutrons. Therfore, C 12 and C 14 are ___________________ of carbon.
isotopes
400
What type of bond shares electrons equally?
Covalent bond
400
A soltion that has a high amount of Hydrogen (H+) ions is considered to be an ____________________.
acid
400
An organism's genetic information is stored in which type of macromolecule? a. lipid b. carbohydrate c. protein d. DNA
d. DNA
400
What do we call the minimum amount of energy required to start a chemical reaction?
Activation Energy
500
Sodium (Na) has 11 electrons. What is the easiest way to make a sodium atom stable?
Lose an electron
500
At the end of a chemical reaction, the products contain less energy than the reactants. Thus, energy was released. What type of chemical reaction is this?
Exothermic
500
Why must chemical equations be balanced?
Matter cannot be created or destroyed.
500
What do we call the specific area on an enzyme that binds to a substrate?
Active Site
500
The electrostatic attraction between adjacent water molecules is called a(n) __________________ bond.