2.1a - Polarity & Properties of Water

polar covalent bond

A covalent bond in which electrons are not shared equally

polar molecule

a molecule in which one side is slightly negative and the opposite side is slightly positive

adhesion

An attraction between water and a molecule of different substances

cohesion

An attraction between two water molecules

capillary action

the combined force of attraction among water molecules and with the molecules of surrounding materials

surface tension

the force that acts on the surface of a liquid and that tends to minimize the area of the surface

high specific heat

it takes a high amount of energy to change the temperature of water

hydrogen bond

weak attraction between a hydrogen atom and another atom

less dense as a solid

water forms crystal like bonds when it freezes putting the molecules at fixed distances from each other

universal solvent

has the ability to dissolve most substances given enough time because of its polar nature

solution

a homogeneous mixture of two or more substances

solute

the substance that is dissolved in a solution.

solvent

the liquid substance capable of dissolving other substances

pH

the measurement of the concentration of hydrogen ions in a solution, how acidic or basic a substance

acid

A substance that increases the hydrogen ion concentration of a solution, pH less than 7.0

base

A substance that decreases the hydrogen ion concentration in a solution, pH greater than 7.0

buffer

mixtures that can react with acids or bases to keep the pH within a particular range

proton

a positively charged subatomic particle found in the nucleus of an atom

electrons

negatively charged subatomic particles that orbit the nucleus of an atom, playing a key role in chemical bonding.

neutron

a subatomic particle with no charge, found in the nucleus of an atom, and contributing to its mass.

covalent bond

chemical bond formed by the sharing of electrons

ionic bond

chemical bond formed by the exchange of electrons

isotope

versions of atoms with different numbers of neutrons

ion

versions of atoms with a positive or negative charge

Octet Rule

principle that atoms tend to bond in a way that makes their outer electron shell complete with eight electrons, leading to greater stability.

radioactive decay

the process by which unstable atomic nuclei lose energy by emitting radiation, leading to the transformation into different elements or isotopes.

half-life

the time required for half of the radioactive atoms in a sample to decay into another element or isotope.

atomic nucleus

the central part of an atom, consisting of protons and neutrons, which contains most of the atom's mass.

atomic number

the number of protons in the nucleus of an atom, which determines the element's identity and its position in the periodic table.

atomic mass

the weighted average mass of an element's isotopes, measured in atomic mass units (amu).

high heat of vaporization

the amount of energy required to change a substance from liquid to gas, reflecting water's ability to absorb significant heat before evaporating.