Unit 1: Chemical Foundations

Question 1

What is the definition of chemistry?

Answer 1

The natural brand of sciences dealing with the composition, properties and reactions of matter using micro and macroscopic perspectives.

Question 2

What are the 3 branches of chemistry?

Answer 2

• Physical Chemistry
• Inorganic Chemistry
• Organic Chemistry

Question 3

What are the 2 goals of chemistry?

Answer 3

Accuracy and Precision

Question 4

What is accuracy?

Answer 4

Accuracy is the level to which the experimental/determined value agrees with a known/theoretical value

Question 5

How is accuracy measured and what is the formula for it?

Answer 5

-Using percent error
- [(exp-theo)/theo] * 100%

Question 6

What should the percent error be for high school students?

Answer 6

It should be less than or equal to 10%

Question 7

What is an example of accuracy?

Answer 7

The closer an arrow is to the center of a dartboard, the more accurate it is

Question 8

What is the definition of precision within a set of numbers?

Answer 8

The smaller the difference within a set, the higher the precision

Question 9

What is the definition of precision with regards to tools?

Answer 9

• The smaller the window for error in a tool, the higher its precision
• In measurement tools, the precision is indicated by plus or minus half the smallest unit available

Question 10

What is the definition of precision within individual measurements?

Answer 10

As indicated by significant figures, the greater the number of sig. figs, the greater the precision

Question 11

What is the scientific method?

Answer 11

A systematic process with one input variable, and one output variable, while all the other variables are controlled

Question 12

List the steps of the scientific method

Answer 12

• ask a question
• form an hypothesis
• design an experiment
• do an experiment
• make observations
• analyze
• draw a conclusion

Question 13

Why is creativity important in the scientific method?

Answer 13

It is important when asking a question, forming an hypothesis, finding observations and forming a conclusion.

Question 14

What makes a good experiment?

Answer 14

• It would be a slow and systematic process
• You have to identify the variables
• Be clear on what you are ultimately measuring

Question 15

What is an experiment?

Answer 15

Something that involves a new input variable

Question 16

What is a trial?

Answer 16

• A change in the level of the independent variable involved in an experiment
• Often 7 trials are done in an experiment

Question 17

What is a test?

Answer 17

• A repeat of a trial to ensure reliability of the data.
• Often 3 tests are done for each trial and the average is considered the true value

Question 18

What are the 2 types of observations?

Answer 18

Qualitative and quantitative

Question 19

What is a qualitative observation?

Answer 19

An observation related to the quality of the objects in question. They are stated in full sentences and they don’t have measurements

Question 20

What is a quantitative observation?

Answer 20

An observation related to the quantity of the objects and is the actual measurements of the objects in question.

Question 21

What is a significant figure?

Answer 21

A number that communicates a magnitude with certainty

Question 22

What is scientific notation?

Answer 22

A standardized method of representing the sig. figs of a given measurement using powers of ten

Question 23

What are the 7 fundamental quantities and their units?

Answer 23

• mass (g)
• time (secs)
• temperature (kelvin)
• length (meters)
• amount of substance (mol)
• electric current (amperes)
• luminous intensity (candela)

Question 24

What is a derived unit?

Answer 24

A unit formed by the combination of one or more fundamental units

Question 25

State 3 derived units

Answer 25

- volume (cm^3) - density (g/mL) - force (kg m/s)

Question 26

What are the 2 modes volume can be measured by?

Answer 26

Capacity mode and Cubic mode

Question 27

State 3 units in capacity and cubic mode and what they are used to measure

Answer 27

Cubic mode: used for solids - cm^3 - dm^3 - m^3 Capacity mode: used for fluids - mL - L - kL

Question 28

1cm^3 = 1 __L 1dm^3 = 1 __L 1 m^3 = 1 __L

Answer 28

1cm^3 = 1 mL 1dm^3 = 1 L 1 m^3 = 1 kL

Question 29

List the prefixes from tera- all the way to pico- with their unit and power of ten

Answer 29

Tera - 10^12 - T Giga - 10^9 - G Mega - 10^6 - M KIlo - 10^3 - k Hecto - 10^2 - h Deca - 10^1 - da Deci - 10^-1 - d Centi - 10^-2 - c Milli - 10^-3 - m Micro - 10^-6 - μ Nano - 10^-9 - n Pico - 10^-12 - p

Question 30

What is the size of an atom and what is it called

Answer 30

It is called an Angstrom (Å) and it is 10^-10