Unit 1 Lab Safety and Scientific Notation

Question 1

What are hazard symbols?

Answer 1

images that warn people of hazardous substances/materials

Question 2

How are hazard symbols helpful?

Answer 2

help people quickly identify substances/materials that may cause harm

Question 3

What is PPE? Name examples.

Answer 3

Personal Protective Equipment

ex. goggles, close-toed shoes, apron, masks, long pants, gloves

Question 4

What would you do if there was a fire in the lab?

Answer 4

let the teacher know

Question 5

What do you do if you get a chemical in your eyes?

Answer 5

go to the eye wash station for at least 15 minutes

Question 6

How do you dispose of chemicals?

Answer 6

dispose according to instructions by your teacher

Question 7

What is a fume hood?

Answer 7

a type of local exhaust ventilation device

Question 8

Why do we need a fume hood?

Answer 8

protects people from inhaling hazardous substances

Question 9

What is scientific notation?

Answer 9

a way of expressing numbers that are too large or too small

Question 10

How is scientific notation useful?

Answer 10

easily calculate numbers that are too large or too small and the ability to represent them in compact ways

Question 11

How is scientific notation different from standard notation?

Answer 11

standard notation does not include the usage of exponents

Question 12

How to convert scientific notation to standard notation:

Answer 12

move the decimal places x times to the left/right depending on the exponent

Question 13

How to convert standard notation to scientific notation:

Answer 13

find the coefficient ( 1 < number < 10)
find the exponent value by the amount of decimal places needed to move

Question 14

How to count significant figures in a number with a decimal

Answer 14

count from left to right starting from the first NON-ZERO number

Question 15

How to count significant figures in a number without a decimal

Answer 15

count from right to left starting from the first NON-ZERO number

Question 16

Rule for significant numbers in scientific notation

Answer 16

All digits INCLUDING zeroes in the coefficient are significant

Question 17

Addition and Subtraction with significant figures

Answer 17

the answer will have the same amount of DECIMAL PLACES as the number with the LEAST amount of decimal places

Question 18

Multiplication and Division with significant figures

Answer 18

the answer will have the same amount of SIGNIFICANT FIGURES as the number with the LEAST amount of sigfigs

Question 19

What is accuracy?

Answer 19

how close you are to the actual value

Question 20

What is precision?

Answer 20

how close your experimental values are

Question 21

Can you identify if a set of results is accurate/precise?

Answer 21

If the results are within 1-5% error

Question 22

What is percent error?

Answer 22

the most common way of measuring an error and the easiest way to understand errors

Question 23

Percent Error Formula

Answer 23

(estimated-actual)/actual * 100

REMEMBER THE RULES

Question 24

What can sources of error be in an experiment?

Answer 24

physical errors in the measuring device, improper or sloppy use of measuring device, ambient conditions(temperature, pressure)

measuring in the wrong unit, small bubbles in the thermometer