Science Exam: Chemistry & Electricity

What are the five points of the particle theory?

1. All matter is made up of particles. 2. The spaces between the particles are large compared to the particles themselves. 3. All particles of one substance are the same, different substances are composed of different types of particles. 4. The particles are in constant motion. 5. Physical properties are characteristics that can be measured or observed.

Fill in the Blank: A characteristic that you can measure and observe without needing a chemical property is called a __________.

Physical property.

What indicates a chemical change?

A chemical change results in the formation of a new substance and changes the identity of a pure substance.

List five signs of a chemical change.

1. Heat has been absorbed or given off. 2. Light has been given off. 3. A precipitate forms. 4. A gas forms or has an odor. 5. A new colour appears.

Fill in the Blank: Water (H2O) has __________ atoms in total.

2 hydrogen and 1 oxygen atom.

What are the three types of subatomic particles?

Protons, neutrons, and electrons.

Define Atomic Number.

The atomic number is the number of protons in the nucleus of an atom.

Fill in the Blank: Similar charges __________ each other, while opposite charges __________ each other.

repel; attract.

What is an electrical insulator?

An electrical insulator is a material in which charges cannot move easily.

Fill in the Blank: According to Ohm's Law, __________ = Voltage / Resistance.

Current.

Define Voltage in the context of electrical circuits.

Voltage, also known as potential difference, is the difference in electrical potential energy in two places in a circuit.

What happens when two neutral substances are rubbed together?

One becomes positively charged (loses electrons) and the other becomes negatively charged (gains electrons).

Fill in the Blank: The mass of a proton is approximately __________ u.

1u.

What characterizes a good electrical conductor?

Electrons move easily within the material.

What does Ohm’s Law state?

Ohm’s Law states the relationship between voltage, current, and resistance.

Fill in the Blank: A gas forms or has an odor is a sign of __________.

Chemical change.