An electrically neutral atom bears what trait?
|A)||It contains protons in its nucleus.|
|B)||It contains the same number of protons and neutrons.|
|C)||It contains the same number of electrons and protons.|
|D)||It contains electrons in its electron shells.|
Isotopes of the same element vary in the number of _______________ they contain.
|B)||neutrons in their nuclei|
Radioactive isotopes emit energy or particles until they reach a stable form. Which type of radiation emitted by a radioactive isotope can be the most penetrating, and thus the most damaging, to living things?
Ionic bonds tend to form between ____________________.
|A)||atoms that have become electrically, and oppositely, charged|
|B)||atoms that share a single pair of electrons|
|C)||atoms that share two pairs of electrons|
|D)||hydrogen and oxygen atoms that bear weak but opposite charges|
Which of these molecular formulas represents both a molecule and a compound?
Chemical reactions occur as bonds are formed or broken between molecules. The molecules that are changed by a reaction are called _______________.
The reaction NaCl # Na+ + Cl-, as written, represents what type of reaction?
Electrolytes that release hydrogen ions (H+) in water are called ________________.
A substance with a hydrogen ion concentration of 0.000001 g/L has a pH of ___________.
Animal "starch," or _______________, consists of branched chains of sugar units and functions to store energy.
The type of lipid responsible for forming the basic bilayer structure of a cell membrane is a _________________ molecule.
A fatty acid in which the carbon atoms are all linked by single carbon- carbon bonds is said to be _________________.
Choose the correct statement about proteins and their structure.
|A)||Hydrogen bonding rarely occurs in proteins.|
|B)||Most proteins are made from a short chain of amino acids.|
|C)||A denatured protein is equally effective as the protein in its original shape.|
|D)||A protein's conformation determines its function.|
Myoglobin, hemoglobin, and many enzymes are ________________ proteins.
DNA contains each of the following components, except ______________.
|B)||a single polynucleotide chain|
The smallest unit of matter is the _____.
Which of the following does not belong with the others?
What is the sum of the neutrons plus protons equal to?
Which of the following is not as abundant as the others in living cells?
Which element has the nuclear configuration of 12/6?
The symbol Na+ is used to describe a sodium _____.
Of the following, which represents an organic compound?
Whenever a partially charged hydrogen comes near a partially charged oxygen on another atom, a _____ bond is formed.
Water tends to dissociate, forming ions; which pH value indicates that the [H+] equals the [OH-]?
Which of these is the correct formula for a strong base?
At what pH is a solution completely acidic? ____