The Language of Composition: Reading, Writing, Rhetoric
2nd EditionLawrence Scanlon, Renee H. Shea, Robin Dissin Aufses
661 solutions
Technical Writing for Success
3rd EditionDarlene Smith-Worthington, Sue Jefferson
468 solutions
Technical Writing for Success
3rd EditionDarlene Smith-Worthington, Sue Jefferson
468 solutions
Technical Writing for Success
3rd EditionDarlene Smith-Worthington, Sue Jefferson
468 solutions
Which of the following best defines covalent bonds?
The bond formed when shared electrons occupy a single orbital common to both atoms within a molecule
Correct
Electron sharing produces molecules in which the shared electrons occupy a single orbital common to both atoms, which constitutes a covalent bond.
Buffers help to stabilize blood pH.
True
False
True
Correct
Buffers are essential for stabilizing the pH of body fluids (such as blood). Note: buffers cannot prevent a change in pH, they can only resist or minimize the change (if acids or bases are added to the buffered solution).
Which of the following is FALSE?
Matter exists in solid, liquid, and gaseous states.
With some exceptions, matter can be seen, smelled, and felt.
The weight of matter
remains constant wherever it is located.
The mass of matter remains constant wherever it is located.
The wight of matter remains constant wherever it is located.
Correct
The mass of an object is equal to the actual amount of matter in the object, and it remains constant wherever the object is. In contrast, weight varies with gravity. Matter is anything that occupies space and has mass. With some exceptions, it can be seen, smelled and felt.
Matter exists in solid, liquid, or gaseous states.
Choose the correctly matched pair.
amino acid: carbohydrate
monosaccharide: lipid
nucleotide: DNA
glycerol and fatty acids: RNA
nucleotide: DNA
Correct
DNA and RNA are nucleic acids; they are built from nucleotides.
Organic compounds are covalently bonded and they always contain oxygen.
True
False
False
Correct
Organic compounds are covalently bonded and they always contain carbon; they often contain oxygen as well.
Atomic number is equal to the number of neutrons in an atom's nucleus.
True
False
False
Correct
The atomic number of any atom is equal to the number of protons, not neutrons, in its nucleus.
Which of the following is NOT a difference between a compound and a mixture?
Mixtures are homogeneous while compounds are heterogeneous.
Mixtures can be separated by physical means, for example, straining, filtering, or evaporation. Compounds can only be separated into their constituent atoms by chemically breaking bonds.
No chemical bonding occurs between the components of a mixture. The properties of atoms and molecules are not changed when they
become part of a mixture.
Some mixtures are homogenous, while others are heterogeneous. All compounds are homogeneous.
Mixtures are homogeneous while compounds are heterogeneous.
Correct
Mixtures differ from compounds in several important ways. (1) The chief difference between mixtures and compounds is that no chemical bonding occurs between the components of a mixture. The properties of atoms and molecules are not changed when they become part
of a mixture. (2) Depending on the mixture, its components can be separated by physical means, straining, filtering, evaporation, and so on. Compounds, by contrast, can be separated into their constituent atoms only by chemical means (breaking bonds). (3) Some mixtures are homogenous, while others are heterogeneous. All compounds are homogeneous.
Nonpolar molecules are the result of unequal electron pair sharing.
True
False
False
Correct
Polar molecules are the result of unequal electron pair sharing. Nonpolar molecules are electrically balanced due to the equal sharing of electrons between the atoms of the molecules.
Which of the following is NOT one of the three major types of chemical reactions?
decomposition
hyperbolic
synthesis
exchange
Hyperbolic
Correct
Most chemical
reactions exhibit one of three recognizable patterns. They are either synthesis, decomposition, or exchange reactions.
Water ________.
can form hydrogen bonds
Correct
Due to its polar nature, water is able to form hydrogen bonds. In fact, many of the special properties of water derive from its extensive hydrogen bonding capacity. In addition, water has a high heat capacity and is considered a universal
solvent since it dissolves more substances than any other known solvent.
Which four elements comprise approximately 96% of our body weight?
carbon, oxygen, hydrogen, and nitrogen.
Correct
Four elements: carbon, oxygen, hydrogen, and nitrogen make up about 96 percent of our body weight; 20 others are present in the body, some in trace amounts.
What are the two fundamental roles of DNA?
To provide the instructions for protein synthesis, and replicate itself before cell division
Correct
DNA has two fundamental roles: (1) to replicate itself before the cell divides, ensuring that all genetic information in the descendant cells is identical; and (2) to provide the basic instructions for building every protein in the body.
Which of the following is TRUE regarding the pH of a solution?
The fewer hydroxyl ions in a solution, the more basic the solution is.
The fewer hydrogen ions in a solution, the more acidic the solution is.
The more hydroxyl ions in a solution, the more acidic the solution is.
The more hydrogen ions in a solution, the more acidic the solution is.
The more hydrogen ions in a solution, the more acidic the solution is.
Correct
The more hydrogen ions in a solution, the
more acidic the solution is.
Which of the following is TRUE of atomic weight?
Atomic weight of an element is approximately equal to the mass number of its most abundant isotope.
Correct
Atomic weight is an average of the relative weights (mass numbers) of all the isotopes of an element, taking into account their relative abundance in nature. As a rule, the atomic weight of an element is approximately
equal to the mass number of its most abundant isotope.
The pH scale ________.
is based on the concentration of hydrogen ions in a solution
Correct
The pH scale, which ranges from 0 to 14, is a logarithmic scale based on the concentration of hydrogen ions in a solution.
Which of the following forms of energy travels in varying wavelengths, such as visible light, infrared waves, radio waves, ultraviolet waves, and X-rays?
electromagnetic energy
Correct
Radiant energy, or electromagnetic energy, travels in waves. These waves, which vary in length, are collectively called the electromagnetic spectrum. They include visible light, infrared waves, radio waves, ultraviolet waves, and X rays.
Which of the following is NOT a subatomic particle?
proton
electron
molecule
neutron
Molecule
Correct
Atoms are comprised of subatomic particles: protons, electrons and neutrons. Most atoms do not exist in the free state, but instead are chemically combined with other atoms. Such a combination of two or more atoms held together by chemical bonds is called a molecule.
ATP is an unstable, high-energy molecule that provides body cells with a form of energy that is immediately usable.
True
False
True
Correct
ATP is the primary energy-transferring molecule in cells, and it provides a form of energy that is immediately usable by all body cells. Chemically, the triphosphate tail of ATP can be compared to a tightly coiled spring ready to uncoil with tremendous energy when the catch is released. Actually, ATP is a very unstable high-energy molecule because its three negatively charged
phosphate groups are closely packed and repel each other.
Which of the following is NOT one of the three basic steps involved in enzyme activity?
The substrate absorbs chemical energy from the enzyme after binding to its active site.
The enzyme's active site binds to the substrate(s) on which it acts, temporarily forming an enzyme-substrate complex.
The enzyme releases the product(s) of the reaction.
The enzyme-substrate complex
undergoes internal rearrangements that form the product(s).
The substrate absorbs chemical energy from the enzyme after binding to its active site.
Correct
Enzymes do not provide energy to their substrates. In fact, enzymes are completely unchanged by their catalytic role and can act again and again.
Which of the following best describes an isotope?
Structurally variant atoms, which have the same number of protons and electrons, but differ in the number of neutrons they contain
Correct
Nearly all known elements have two or more structural variations called isotopes, which have the same number of protons and electrons, but differ in the number of neutrons they contain.
The major function of RNA is to carry out the genetic instructions for protein synthesis.
True
False
True
Correct
The major function of RNA is to carry out the genetic instructions (provided by DNA) for protein synthesis.
Suspensions may also be called emulsions.
True
False
False
Correct
Colloids, not suspensions may also be called emulsions. Colloids are heterogeneous mixtures, meaning their composition is dissimilar in different areas of the mixture. Colloids
often appear translucent or milky and although the solute particles are larger than those in true solutions, they still do not settle out. Suspensions are heterogeneous mixtures with large, often visible solutes that tend to settle out.
What is the difference between kinetic and potential energy?
Kinetic energy is energy in action, while potential energy is stored energy.
Correct
Kinetic energy is
energy in action. We see evidence of kinetic energy in the constant movement of the tiniest particles of matter, as well as in larger objects. Potential energy is stored energy, which has the capacity to do work, but is not presently doing so.