AP Edition Biology Seventh Edition Campbell Reece Chapter 2 Flashcards

3014028629	Matter	Anything that takes up space and has mass	0
3014031035	Elements	A substance that cannot be broken down to other substances by chemical reactions	1
3014041987	Compounds	A substance consisting of two or more different elements combined in a fixed ratio	2
3014033399	Life's essential elements:	Carbon, oxygen, hydrogen, and nitrogen Phosphorus, sulfur, calcium, and potassium are required in smaller amounts	3
3014039678	Trace elements	Required by organisms in only small amounts	4
3014338845	atoms	The smallest unit of matter that still retains the properties of an element	5
3014057864	Protons and neutrons form the...	The atomic nucleus	6
3014060034	Daltons measure...	The mass of atoms and subatomic particles	7
3014049726	The atomic number is based on...	Protons. (All atoms of a particular element have the same number of protons)	8
3014047066	The mass number is based on...	The sum of protons plus neutrons	9
3014044048	Atomic mass is based on...	Total mass. Mainly the weight of protons and neutrons	10
3014061521	Isotopes	Two atoms of an element that differ in number of nuetrons	11
3014065164	Radioactive isotopes	The nucleus decay spontaneously giving off particles and energy - when the decay of leads to a change in the number of protons it becomes a different	12
3014073842	Biologists use radioactive isotopes to...	- date fossils - as tracers through metabolic processes -diagnosing medical disorders	13
3014083222	Energy	The capacity cause change	14
3014085085	Potential energy	The energy matter possesses because of its location or structure	15
3014091042	Matter has a natural tendency to move to the lowest state of potential energy	...	16
3014111992	Electrons in the first shell have the _______ potential energy	Lowest (increases shell by shell)	17
3014127126	The chemical behavior of an atom depends on...	The number of electrons in the outermost shell	18
3014122409	An atom with a completed valence shell is...	Unreactive (inert)	19
3014088391	The more distant the electrons are from the nucleus the ______ the potential energy	Greater	20
3014381624	Chemical bonds	atoms with incomplete valence shells can share or transfer valence electrons	21
3013914609	Covalent bond	The sharing of a pair of valence electrons	22
3013903092	Electronegativity	an atom's attraction for the electrons in a covalent bond	23
3013898608	Nonpolar covalent bond	Equal sharing of electrons	24
3013893033	Polar covalent bond	(unequal sharing)	25
3013888069	Ionic bonds	When an atoms transfer electrons (severely unequal)	26
3013918184	Ion	A charged atom	27
3013922036	A cation is a ...	Positive ion	28
3013918185	An anion is a ...	Negative ion	29
3013938673	Salts are...	Ionic compounds	30
3014131955	Hydrogen bonds occur when...	A hydrogen atom covalently bonded to one electronegative atom is also attracted to another electronegative atom	31
3014137351	Weakest bonds are...	Ionic bonds or hydrogen bonds	32
3014139189	Strongest bonds are...	Covalent bonds	33
3014145123	Van der Walls interations	are interactions between molecules that are close together as a result of asymmetrical electrons	34
3014095521	An electron can change shells by absorbing or losing energy. when they absorb energy, they move to a farther shell. When they lose energy, they "fall back" to a closer shell. The loss of energy is released as...	Heat	35
3015181458	Molecules with similar shapes can have similar biological effects because...	biological molecules recognize and interact based on molecular shape	36
3015186354	Chemical reactions are...	the making and breaking of chemical bonds	37
3015195241	Chemical equilibrium	when the forward and reverse reaction rates are equal	38