Chapter 2 Flashcards
Chemistry
What is a compound?
A molecule with two or more atoms of different elements that are chemically bonded together through the interaction of electrons in their valence energy levels (valence shells)
What is a molecule?
A grouping of two or more atoms held together by chemical bonds
The base unit of a compound
What is a bond?
Weak or strong electrical attraction that holds atoms in the same vicinity
What is an ion?
An atom with an electrical charge (positive or negative)
What is a cation?
Positively charged ion
What is an anion?
Negatively charged ion
What is an atom?
Smallest quantity of an element that retains the its unique properties
What is the octet rule?
An atom will give up, gain, or share electrons with another atom so it ends up with a full valence shell, or at least 8 electrons in its valence shell
What is a valence shell/valence energy level?
Atom’s outermost electron ring/shell
Most strongly governs the tendency of an atom to participate in chemical reactions
What is an electron shell?
The layer of electrons that encircle the nucleus at a distinct energy level
What is matter?
The substance of the universe. Anything that occupies space and has mass
What is mass?
The amount of matter contained in an object, that is constant
What is weight?
The effect of gravity’s pull on an object’s mass
What is an element?
Pure substance that cannot be created or broken down by ordinary chemical means. The primary constituent of matter.
What are the subatomic particles?
Protons, neutrons, electrons
What is atomic mass/mass number?
Mass of protons + neutrons
What makes up the nucleus?
Protons and electrons
What is an atomic number?
The number of protons in the nucleus
What is an isotope?
One of the different forms of an element. Has a varying number of neutrons.
What is a heavy isotope?
Has more than the usual number of neutrons. Usually unstable and radioactive.
What is a radioactive isotope?
Nucleus actively decays and gives off subatomic particles and electromagnetic energy
What is half life?
The time it takes for 1/2 of an isotope to decay
What is chemistry?
The branch of science that deals with the identification of substances of which matter is composed. Investigation of their properties and the ways they interact. The use of these properties to form new substances.
What are the 3 phases of matter?
Solid, liquid, gas
What is a liquid?
Matter where particles bounce and move away from each other. Takes on the shape of its container.
What is a solid?
Particles of matter that are tightly packed. Motion is like vibration because particles have no space to move. Has a definite shape
What is a gas?
Particles of matter that are far apart and less likely to hit each other. Takes on the shape of its container and can be compressed.
What is energy?
Puts matter in motion
The capacity to do work
What are the most common elements in the body?
Oxygen
Hydrogen
Carbon
Nitrogen
Calcium
Phosphorous
What is AMU?
Atomic mass unit
The mass of one proton or one electron
What is a mixture?
Substance that contains two or more components that can be relatively easily separated using physical means. Not bound together.
What are the types of mixtures?
Solution, colloid, suspension
What is a solution?
Transparent mixture. Small and invisible solute particles dissolved in a solvent that do not settle out, do not scatter light, and are not acted on by gravity.
What is a colloid?
Milky or translucent mixture with larger but invisible particles that do not settle out and are not acted on by gravity. They scatter light. Heterogenous.
What is a suspension?
Mixture with particles that are visible, settle out, and are acted on my gravity. Heterogenous and translucent.
What are the three types of chemical bonds?
Ionic, covalent, hydrogen
What is an ionic bond?
An ongoing association between opposite charged ions. Formed when valence electrons are donated.
Weak bond.
What is a covalent bond?
Molecules share electrons in a mutually stabilizing relationship to satisfy the octet rule. They do not lose or gain electrons permanently, they just move back and forth between atoms. Strong bonds that contain potential energy.
What is a nonpolar covalent bond?
Electrons in the atoms’ overlapping orbitals are shared to fill both valence shells. Electrically balanced.
What is a polar covalent bond?
Occurs when atoms share electrons unequally. Contains regions with opposite charges. Atoms orient themselves according to attractions.
What is a hydrogen bond?
A weakly positive hydrogen atom already bonded to one electronegative atom is attracted to another electronegative atom from another molecule.
What are the special characteristics of water?
Cohesion, adhesion, thermal stability, solvency, chemical reactivity
What is kinetic energy?
The energy matter possesses because of it’s motion. Powers matter in motion.
What is potential energy?
Energy matter possesses because of it’s positioning and structure. The energy of position.
What is chemical energy?
The energy released by chemical bonds breaking
What is exergonic?
Reactions that release more energy than they absorb (catabolic)
What is endergonic?
Reactions that absorb more energy than they release and require energy input. Resulting molecule stores chemical energy and energy from the original substance. (anabolic)
What is mechanical energy?
Stored in physical systems and directly powers matter movement