Bio Chapter 2

Isotopes

________- have the same number of protons and.

Compounds

________- substances that contain two or more elements in a.

Cohesion

________- tendency of molecules of the same kind to stick.

Ions

________- atoms or molecules that are electrically.

Radioactive isotope

________- one in which the nucleus.

Element

________- a substance that can not be broken.

Proton

________- is positively charged.

Evaporative

________ cooling- when a substance.

Chemical bonds

________- atoms staying close together, held by attractions.

Solute

________- whats being dissolved.

Solution

________- a liquid consisting of a homogeneous.

Buffer

________- minimizes changes in pH.

Mass

________- a measure of the amount of material in an.

Hydrogen bonds

________- weak electrical attractions due to the polarity of water.

Atom

________- is the smallest unit of matter.

Electron

________- is negatively charged.

Matter

________- anything that occupies space and has mass.

Reactants

________- the starting materials.

Neutron

________- is electrically ________.

Aqueous solution

________- when water is the solvent.

H

Base- accepts ________ and removes it from a solution.

Ionic bonds

________- formed between oppositely charged.

PH scale

________- measurement of the hydrogen ion H concentration in a solution.

Covalent bond

________- forms when two atoms share one or.

Polar molecule

________- one with an uneven distribution of charge.

Chemical reactions

________- changes in the chemical composition of matter.

Molecule

________- group of atoms.

Ionic

________ compounds- held together by ionic bonds.

Matter

anything that occupies space and has mass

Mass

a measure of the amount of material in an object

Element

a substance that cannot be broken down into other substances by chemical reactions

Trace elements

required in only very small amounts and are essential for life

Compounds

substances that contain two or more elements in a fixed ratio

Atom

is the smallest unit of matter

Proton

is positively charged

Electron

is negatively charged

Neutron

is electrically neutral

Atomic number

All atoms of a particular element have the same unique number of protons

Mass number

the sum of the number of protons and neutrons in its nucleus

Isotopes

have the same number of protons and behave identically in chemical reactions, but they have different numbers of neutrons

Radioactive isotope

one in which the nucleus decays spontaneously

Chemical bonds

atoms staying close together, held by attractions

Ions

atoms or molecules that are electrically charged as a result of gaining or losing electrons

Ionic bonds

formed between oppositely charged ions

Ionic compounds

held together by ionic bonds

Covalent bond

forms when two atoms share one or more pairs of electrons; strongest bond, holds toms together in a molecule

Molecule

group of atoms

polar molecule

one with an uneven distribution of charge

hydrogen bonds

weak electrical attractions due to the polarity of water

chemical reactions

changes in the chemical composition of matter

reactants

the starting materials

products

the end materials

water content in cells

70-95%

cohesion

tendency of molecules of the same kind to stick together

Evaporative cooling

when a substance evaporates and the surface of the liquid remaining behind cools down

solution

a liquid consisting of a homogeneous mixture of 2 or more substances

solvent

dissolving agent

solute

whats being dissolved

solution

resulting mixture

aqueous solution

when water is the solvent

acid

releases H

base

accepts H and removes it from a solution

pH scale

measurement of the hydrogen ion H concentration in a solution

buffer

minimizes changes in pH