Chemistry - Science 8 review

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What is matter?

Anything that has mass and volume

What is mass?

The amount of matter in a substance

What are the units for mass?

Grams (g) and kilograms (kg)

What is volume?

The amount of space a substance or object occupies

What are the units for volume?

Liters (L)

What is the basic unit of matter?

The atom

What are atoms made of?

Neutrons, protons, and electrons

What are neutrons and protons made of?

Quarks

What is the difference between an atom and a molecule?

Atoms are singular particles and molecules are two or more atoms bonded together

What is an element?

A substance that contains one type of atom

Where can elements be found?

On the periodic table

What are elements (atoms, molecules, giant structures)?

Single atoms or molecules

What are examples of elements?

Gold, oxygen

What is a compound?

A substance that contains two or more types of atoms

What are compounds (atoms, molecules, giant structures)?

Molecules or giant structures

What are some examples of compounds?

Salt, sodium chloride

What is a chemical change?

A change in matter that happens when substances combine to form new substances and the properties of the new substance are different from those of the original substance

Most chemical reactions are ____________

Irreversible (not all)

Are physical changed reversible?

Yes

Is crumpling a sheet of paper a physical or chemical change?

Physical

Is an ice cube melting a physical or chemical change?

Physical

Is a match burning a chemical or physical change?

Chemical

Is dissolving sugar in water a physical or chemical change?

Physical

Is making toast a physical or chemical change?

Chemical

Is boiling an egg a physical or chemical change?

Chemical

Is iron rusting a physical change or a chemical change?

Chemical

Is digesting food a chemical or physical change?

Chemical

What are 5 signs that a chemical change has occured?

Precipitation, bubbles/fizzing, colour change, temperature change, light is given off

What is percipitation?

When a solid is formed from two liquids

What are the four common states of matter?

Solid, liquid, gas, and plasma

What are the characteristics of a solid?

It has a definite shape and volume

What are the characteristics of liquid?

It takes the shape of it's container or surroundings

What are the characteristics of gas?

Its shape and volume is determined by its surroundings and it fills its container completely

What are the characteristics of plasma?

It is an ionized gas. This means electrons are dissociated from their atomic nuclei

What are some examples of plasma?

Lightning, fluorescent and neon light, and the northern lights

How does a gas turn into plasma?

If the gas gets hot enough, the molecules separate into free roaming atoms. With even more heat, the ionization process begins. The electrons separate from the atoms and freely roam, leaving behind positively charged ions. The mixture of freely roaming negative and positive charges is plasma

How does plasma produce light?

Electric fields accelerate plasma and magnetic fields steer them in circular orbits. When particles in a plasma collide or are accelerated or magnetism, light is generated.

What do we humans use plasma for?

There are plasma TV's and it can be used in hospitals to kill pathogens

What are the four points of the particle model of matter?

1. All matter is made of very small particles
2. There are spaces between the particles and the amount of space depends on the state of matter
3. Particles are always moving
4. The particles are attracted to one another and the strength of the attraction depends on the type of particle

How is the kinetic molecular theory different than the particle model of matter?

The kinetic molecular theory (KMT) includes how matter behaves when the kinetic energy of the particle changes

What is kinetic energy?

The energy of motion

What are the four points in the KMT?

1. All matter is made up of very small particles
2. There is empty space between particles
3. Particles are constantly moving
4. Energy makes particles move

The more energy particles have...

The faster the particles will move and the further the particles will be from each other

How much energy does a solid have and what movement do the particles inside of a solid do?

Particles of a solid have less kinetic energy. They are so tightly packed together, they can only vibrate.

How much energy does a liquid have and what movement do the particles inside of a solid do?

Particles of a liquid have more kinetic energy. They are farther apart and can slide past each other

How much energy does a gas have and what movement do the particles inside of a solid do?

Particles of gasses have the most kinetic energy. They are far apart and can move around quickly. They are bouncing off everything.

What is it called when a solid becomes a liquid?

Melting

What is it called when a liquid becomes a gas?

Evaporation

What is it called when a gas becomes plasma?

Ionization

What is it called when a solid becomes a gas?

Sublimation

What is it called when plasma becomes a gas?

Deionization

What is it called when a gas becomes a liquid?

Condensation

What is it called when a liquid becomes a solid?

Solidification

What is it called when a gas becomes a solid?

Deposition

What are physical properties?

Properties or characteristics that can be observed or measured

What are qualitative properties?

Properties described, not measured

What are some examples of qualitative properties?

State, colour, malleability, and texture

What are quantitive properties?

Properties that can be measured numerically

What are some examples of quantitative properties?

Density, melting/freezing point, boiling/condensing point, and solubility