Science Magazine May 2014 | Page 3

Mix and flow

of matter

DEFINITIONS

Solubility: the mass of a solute that can dissolve in a given amount of solvent to form a saturated solution at a given temperature.

Saturated [solution]: a solution in which no more solute will dissolve in a specific amount of solvent at a specific temperature.

Supersaturated [solution]: a solution hat contains more solute than would normally dissolve at a certain temperature.

Unsaturated [solution]: a solution in which more of the solute could dissolve in a specific amount of solvent at the same temperature.

Solvent: the substance that does the dissolving.

Solute: the substance that gets dissolved.

THE UNIVERSAL

SOLVENT

Water is the universal solvent. It is water’s chemical composition and physical attributes that make it such an excellent solvent.

Water molecules have a polar arrangement of the oxygen and hydrogen atoms - one side (hydrogen) has a positive electrical charge, and the other side (oxygen) has a negative electrical charge. This allows the water molecule to become attracted to many other different types of molecules.

Water can become so heavily attracted to a different molecule, like salt, that it can disrupt the attractive forces that hold the sodium and chloride in the salt molecule together and, thus, dissolve it.

Particle Model of Matter

1) Substances are made of tiny particles

2) All particles in a pure substance are the same. Different pure substances are made of different particles

3) The particles have spaces between them

4) The particles are always in motion. The speed of the particles increases/decreases when the temperature increases/decreases

5) The particles in a substance are attracted to one another. The strenghth of the attractive force depends on the type of particle

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