scoence abeka 5th grade p72-79

Mixture

Consist of two or more substances that are physically combined unlike the molecules in a compound the particles of each substance in a mixture keep their identity

Matter

anything that has volume and has mass

(Sometimes called substance)

Volume

The amount of space that an object takes up

The standard unit of metric measurement for volume

Liter

How many milliliters are in a teaspoon?

5 mL

Graduated

Means the container is divided into equally marked parts, for example a graduated cylinder

Two ways to measure the volume of a solid

1. Length times width times height

2. for irregular solids, you must use water displacement

Water displacement

Place irregular objects in a graduated cylinder measure the difference in milliliters. In the metric system 1 mL on a graduated cylinder is equal to 1 cm³.

Mass

The amount of material in a substance

(Usually measured with a balance)

Metric units of mass and give examples of each

Grams and kilograms

examples: the mass of a paperclip is about 1 g and the mass of a 1 L bottle of water is about 1 kg kilogram

weight

The amount of force gravity exerts on matter

What is the difference between mass and weight?

Mass measures the amount of matter, but weight measures the amount of force gravity exerts on the matter

Density

The amount of matter in a certain volume calculated by dividing its mass by its volume- usually measured in grams per milliliter

Most substances have greater density in a solid form than a liquid form, except

Water- ice floats on top of liquid water

Physical property

Is a characteristic of a substance that can be observed without changing the identity of the substance examples include color, texture, smell, density and ability to conduct electricity

States of matter

Solid liquid or gas. All matter is composed of tiny particles that are always in motion. These particles attract each other. The attraction tends to hold the particles together the motion of the tiny particles and the strength of their attraction determines the substances state of matter.

Solid.

Is the state of matter in which a substance has a definite volume and shape. Particles in a solid do vibrate, but they do not move very much. They have a very strong attraction to each other.

Liquid.

Is the state of matter in which substance has a definite volume, but not a definite shape. Liquid takes the shape of the container that it is in particles in liquids, move more than particles and solids. The attraction between the particles is strong enough to keep the matter from completely spreading apart

Gas.

The state of matter in which substance does not have a definite shape or a definite volume. It takes the shape of its container. Unlike solids or liquids gases can also expand to fill. The volume of their containers. Gases are easily compressed. Gas particles are very active and are only weekly attracted to one another.

Plasma.

A fourth state of matter found in a lightning bolt -can only occur at very high temperatures

Physical change

Is a change in matter that does not form a new substance. Matter cannot be created or destroyed.

An example is solid ice cream melting into a liquid

Melting

The process of a solid changing to a liquid

Melting point

The temperature at which a solid changes to a liquid

Ice melts at

0°C or 32°F

Most metals have very high melting points

Freezing

The process of a liquid changing to a solid (also known as solidifying)

Freezing point

The temperature at which a substance changes to a solid

How are the melting point and freezing point of a substance related?

They are the same temperature

Vaporization

The process of a liquid changing into a gas

Boiling point

The temperature at which a liquid turns into a gas. For example, the boiling point of water is 100°C.

Evaporation.

Another form of vaporization, but occurs when a liquid changes to a gas at a temperature below it’s boiling point evaporation only occurs on the surface of a substance

Condensation.

When a substance changes from a gas to a liquid

Condensation point.

The temperature at which a gas turns into a liquid

What two things determine a substance state of matter

Shape and volume

What are two ways that gases differ from liquids and solids?

Gases have no definite shape. Also, the particles in gases have very weak attraction to one another.

All matter is made up of small particles called

atoms

Element

matter that is made up of only one kind of atom

Molecule

A particle formed when atoms join with other atoms

Compound

Is formed by combining atoms of different elements

Chemical change

Occurs when the atoms in an element for compound combined to form a new substance unlike a physical change a chemical change causes the elements or compounds to lose their individual properties

How is granite an example of a mixture that is not evenly mixed

Each piece of granite may have a different mixture of minerals in it

What are three ways you might separate a mixture

Mixtures are separated by their physical properties:

1 shaking a mixture causes smaller items to fall to the bottom of the container

2 a liquid mixture with two different densities; more dense goes to the bottom, and the less dense can be poured out of the top

3 a mixture of salt and sand can be dissolved in water. The salt will dissolve and can be poured out of the sand.

Solution

is a mixture in which all the substances are spread evenly throughout an example is salt dissolved in water

Dissolving

is the process in which the particles of one substance separate and spread evenly throughout another substance

solute

is the substance that is dissolved

Solvent

is the substance that dissolves the other substance example saltwater water is the solvent

“ universal solvent”

water

in a soft drink, which is the solute and which is the solvent

carbon dioxide is the solute and the liquid is the solvent

Alloys

A mixture of two or more metals and example is a nickel coin. It is made of nickel and copper.

Concentration

Of a solution is the amount of solute that is dissolved in the solvent

Diluted

There is less than a normal amount of solute in the solvent. An example is poorly sweetened tea.

Concentrated

Means the solvent is holding more than a normal amount of solute an example is too sweet sweet tea

Name, three ways to speed up the rate at which a solute dissolves in a solution

1 increase the surface area of the solute ex crush

2 stir the solution

3 heat increases solubility

solubility

the ability of a solvent to dissolve a certain amount of solute