polar molecules

When there is an uneven distribution of charge or electrons shared between atoms.  For instance, in water molecules, oxygen pulls the electrons away from hydrogen. 

acidic solutions

Solutions that contain higher

concentrations of H⁺ ions than pure water

and have pH values < 7.

basic

solutions

Cohesion

• Because of hydrogen bonding, water is extremely cohesive.

Attraction between molecules of the

same substance.

Adhesion

• When measuring water in a glass cylinder, water's clings to the edges of a graduated glass cylinder and is raised up forming a concave meniscus. 

Attraction between molecules of different substances.

Mixture

Material composed of two or more elements or compounds that are physically added together but not chemically combined.

examples:

sugar and sand

Salt and pepper 

Solution

    A.K.A. a homogeneous mixture; when combined, 2 or more substances that mix uniformly.

example:

salt + water

Koolaid mix + water 

Solute

It is the substance, usually solid, that is dissolved in a solution.

example:

Salt in a salt water solution.

Solvent

The substance, often water,

that dissolves something.

Example:

Water dissolves salt to make salt-water.

It also dissolves Koolaid to make a sugary drink. 

Suspensions

When materials do not dissolve when placed in water but separate into pieces so small that they do not settle out.

Some of the most important biological fluids are both solutions and ?. 

Example:

Blood in our body is considered a ? and a solution, because of dissolved and undissolved particles that remain in ? as the blood moves through the body. 

pH scale 

A measurement system invented by chemists to indicate the concentration of H⁺ ions in solution; ranges from 0-14.

See pg 43 for examples 

Buffer

polar molecules

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Hydrogen Bond

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Type of bond that forms between the partially negative oxygen atom & the partially positive hydrogen atom on two different water molecules.

Suspension

Water & flour mixed together:  the undissolved particles are so small they don't settle out.

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