CHEM 2N LEC FIRST QUIZ

• Chemistry is the study of the composition and structure of substances and the reactions they undergo
• Matter is anything that occupies space and has mass
• Mass is the amount of matter in an object, and weight results from the gravitational force acting on an object of a given mass
• An element is the simplest type of matter with unique chemical properties
• An atom is the smallest particle of an element that has the characteristics of that element
• Atoms consist of neutrons, positively charged protons, and negatively charged electrons
• The atomic number is the unique number of protons in each atom of an element. The mass number is the number of protons and neutrons
• Ionic bonding results when an electron is transferred from one atom to another
• A hydrogen bond is a weak attraction that occurs between the oppositely charged regions of polar molecules
• A molecule is two or more atoms chemically combined to form a structure that behaves as an independent unit
• Dissociation is the separation of ions in an ionic compound by polar water molecules
• A synthesis reaction is the combination of reactants to form a new, larger product
• Energy is the capacity to do work. Potential energy is stored energy that could do work, and kinetic energy does work by causing the movement of an object
• The rate of chemical reactions increases when the concentration of the reactants increases, temperature increases, or a catalyst is present
• Acids are proton (hydrogen ion) donors, and bases are proton acceptors
• A neutral solution has an equal number of H+ than OH- and a pH of 7.0
• A salt is formed when an acid reacts with a base
• Buffers are chemicals that resist changes in pH when acids or bases are added
• Oxygen is involved with the extraction of energy from food molecules
• Water stabilizes body temperature, provides protection, is necessary for many chemical reactions, and transports substances
• Carbohydrates provide the body with energy
• Lipids provide energy, are structural components, and regulate physiological processes
• Proteins regulate chemical reactions, are structural components, and cause muscle contraction
• The basic unit of nucleic acids is the molecule, which is a monosaccharide with an attached phosphate and organic base