Unit 1

Question 1

What is the science of properties, structure, and transformation of matter called?

Answer 1

Chemistry

Question 2

What is matter?

Answer 2

Anything with mass and takes up space

Question 3

Can matter be destroyed?

Answer 3

No

Question 4

What is the Law of Conservation of Mass?

Answer 4

In a chemical reaction, matter is neither created nor destroyed, it is transformed into something else.

Question 5

Who first came up with the theory of Law of Conservation of Mass?

Answer 5

Lavoisier

Question 6

What kind of change happens when substances are used up and other compounds are formed to take their place?

Answer 6

Chemical Change

Question 7

What kind of change occurs when the identity of a matter remains the same but involves change in its state?

Answer 7

Physical Change

Question 8

Explain a solid.

Answer 8

Having a definite shape and a definite volume. All particles are very close together.

Question 9

Explain a liquid?

Answer 9

Have an indefinite shape and a definite volume. Particles are not very close together.

Question 10

Explain a gas.

Answer 10

Have an indefinite shape and an indefinite volume. Particles are very far apart and move freely.

Question 11

What are some characteristics of physical properties?

Answer 11

Colour, shape, size, texture, mass, volume, and density.

Question 12

What are some types of changes in physical properties?

Answer 12

Melting, freezing, boiling/vaporization, condensation, ionization, relaxation.

Question 13

What are some signs of a chemical change? Give some examples.

Answer 13

Odor, change in temperature, change in color, formation of bubbles, solids form. Examples: burning, rusting, rotting, tarnishing, etc.

Question 14

What is a chemical reaction?

Answer 14

Atoms from 2 substances combine to form new substances.

Question 15

What type of reaction is this:
2Na + Cl2 –> 2NaCl

Answer 15

Chemical

Question 16

What is a pure chemical substance consisting of one type of atom, which cannot be broken down further called?

Answer 16

Element

Question 17

What is a compound?

Answer 17

Definite and constant composition, same properties under a certain set of conditions.

Question 18

What is a homogenous mixture? Give an example.

Answer 18

Uniform composition and properties throught a sample. It is difficult to see impurities in this mixture. Examples: air, gasoline, salt solutions, etc.

Question 19

What is a heterogeneous mixture? Give an example.

Answer 19

Non-uniform composition and properties throught a sample. Different components are visibly distinguishable from one another. Example: Water and oil mixed.

Question 20

What is exponential notation?

Answer 20

Very large or small numbers based on powers of 10.

Question 21

Which in the exponent and which is the coefficient in: N × 10^n

Answer 21

N: Coefficient
n: Exponent

Question 22

What is a measurement? Give some examples.

Answer 22

A method in determining a physical quantity. Such as length, time, and temperature.

Question 23

Why do we need measurements?

Answer 23

So we can quantify time, distance, plan, schedule, risk assessment, quality and precision.

Question 24

What is accuracy?

Answer 24

How close a measurement is to the true value.

Question 25

What is precision?

Answer 25

The variation seen when measuring the same part repeatedly with the same device.

Question 26

What is density?

Answer 26

Physical property, constant at a given temperature.

Question 27

Why does density change with temperature?

Answer 27

Mass does not change but volume does. Volume increases because molecules move further apart.

Question 28

Since mass is a constant does density increase or decrease as temperature rises?

Answer 28

Density decreases.

Question 29

What temperature is waters max density?

Answer 29

4 degrees Celsius

Question 30

Does the ratio of density of a substance to density of water have units?

Answer 30

No

Question 31

What device is used to measure specific gravity?

Answer 31

A hydrometer.

Question 32

Explain what a hydrometer does.

Answer 32

If specific gravity is higher than 1 substance will sink below water. If lower than 1 substance will float on top of water.

Question 33

What is energy and what are the 2 forms?

Answer 33

Energy is the capacity to do work. Kinetic energy and potential energy.

Question 34

What is kinetic energy?

Answer 34

Energy motion possessed by any moving object. Light, heat, mechanical energies. It is proportional to mass and speed.

Question 35

What is potential energy?

Answer 35

Stored energy. The capacity to move or cause motion due to position. Chemical and nuclear energy.

Question 36

What is the difference between heat and temperature?

Answer 36

Temperature is the kinetic energy of matter: the faster the molecules move, the higher the temp. Heat is a form of energy: the flow of energy from higher to lower temp source.

Question 37

What are the 2 units of measurement for heat?

Answer 37

Metric based unit = calorie (cal) SI based unit = Joule (J)

Question 38

What is a calorie?

Answer 38

Amount of energy required to increase the temperature of 1g liquid water by 1⁰C

Question 39

What is a joule?

Answer 39

The amount of energy it takes to exert force of one Newton over a distance of one meter, or heat emitted by one-watt heater for one second.

Question 40

What is specific heat capacity (c)? And how is it measured?

Answer 40

It is a physical property. The heat required to raise the temperature of 1g of substance by 1⁰C. Measured in cal/g⁰C

Question 41

What is the equation for specific heat?

Answer 41

Q = mc^T Q= heat energy (cal) m= mass (g) c= specific heat (cal/g⁰C) ^T= change in temperature (T final - T initial)