4th Grade Science Chapter 9

English units for Weight

Ounces and Pounds

The 3 stages of matter

Solid, liquid and gas. Each has particles with different physical properties.

Weight

Measures the amount of gravity between an object and a planet.

Newton

Metric unit for Weight

Property

A characteristic that you can observe.. One way to describe matter is by its properties. Color, shape & size are examples.

Gravity

A force, or pull, between all objects.

The Metric System

A measurement system based on units of ten.

Change of State

A physical change in which one state of matter changes to another. Volume may change, mass stays the same. Example - solid changing to a liquid.

Differences between physical change and chemical change

A physical changes begins and ends with the same type of matter. The physical properties of the matter change. (ice cube to water, sculpting a rock). In a chemical change, you start with one kind of matter and end up with another. When iron gets wet and reacts with the oxygen in the air, rust is formed. This is a chemical change (chemical reaction).

Length

An object's length is the number of units that fit from one end to another. One way to measure length is to use a ruler.

Matter

Anything that takes up space and has mass. Most things are made of matter. The air we breathe, the book you're reading are made of matter. Light and heat are not matter because they do not take up space.

Chemical Change

Begins with one kind of matter and ends with another. Also known as a chemical reaction. Always gives off energy or use energy. An example is the change from iron to rust Cooking and baking cause this in food. When vinegar is mixed with baking soda, carbon dioxide gas is released. This is a ...

Area

Describes the number of unit squares that cover a surface. Multiply the length by the width.

A Liquid

Does not have a definite shape,it takes the shape of its container. Takes up a definite amount of space. The particles of matter can move more than in a solid, they are farther apart than in a solid

A Gas

Does not have a definite shape. In that way it is like a liquid. Unlike a liquid, it does not take up a definite amount of space. The particles of matter move about freely. The particles move farther apart from one another to fill the space around them. If there is less space to fill, the particles are closer together. A gas always spreads out to fill its container.

A Solid

Has a definite shape and takes up a definite amount of space. The particles are packed tightly together in a regular pattern.

Volume

How much space an object takes up. We measure volume by counting the number of cubic units in an object. We can also measure volume with tools like a graduated cylinder.

How water changes state

If you add energy (heat) to an ice cube, its particles move faster. If the particles gain enough energy, the solid changes to a liquid. Melting is a change of state from a solid to a liquid. If you add energy (heat) to water, it can change to a gas, water vapor. Its particles move very fast.

Differences between mass and weight

Mass is a measurement of how much matter is in an object; weight is a measurement of how hard gravity is pulling on that object. Your mass is the same wherever you are--on Earth, on the moon, floating in space--because the amount of stuff you're made of doesn't change. But your weight depends on how much gravity is acting on you at the moment; you'd weigh less on the moon than on Earth.

Mass

The amount of matter making up an object. Mass is measured in units called grams or kilograms. To measure mass, you use a tool called a balance.

Evaporation

The change of a liquid to a gas without boiling. The suns energy causes water in lake, rivers or oceans to...

Width

The number of units that fit across an object.

Physical Change

The physical properties of the matter change but the matter is still the same substance. An ice cube melts, flatten a piece of clay. Begins and ends with the same type of matter.

Density

The relationship between mass and volume. The mass of the matter in a given space. The amount of mass in a unit of volume. To find the density of an object, divide its mass by its volume. Mass is in grams and volume is in cubic centimeters. The measure for density is grams per cubic centimeter (g/cm3)

Buoyancy

The upward force of a liquid or gas on an object. All objects are buoyant. Some objects are so buoyant that then can float.

Standard Unit

Used when measuring; it is a measurement that people agree on.