Lecture 1

Scientific Notation

100

Express in Scientific Notation (do not round to sig figs):

0.3543 

3.543x10^-1 

200

Express in Scientific Notation (do not round to sig figs): 

34100000

3.4100000x10⁷

300

Write in standard notation:

8.47x10⁵

847,000

400

Express in Standard Notation

5.52x10⁶

5,520,000

500

Express in Scientific Notation (round to all significant figures): 

102,000,000

1.02x10⁸

*BONUS*: why are some 0s significant while others are not?

Uncertainty

100

Which number is uncertain in this measurement? 

47.983

3 (the last digit is estimated/uncertain)

200

Given an instrument with markings every 0.1g, to which place do we report/estimate? 

(ones, tenths, hundredths, etc.)

hundredths

(report to one digit beyond given instrument)  

300

What is the reported value for Ruler A? 

CHECK PICTURE GIVEN 

2.55

3rd digit may vary since it is an estimate. 

400

What is the reported value for the ruler given? (cm)

1.25 cm 

* last value may vary; it is estimated* 

500

What is the reported value of the instrument given?
(markings every 1mL)

SEE GIVEN PICTURE 

21.6

* Last digit is estimated may vary* 

* When taking measurements using graduated cylinders, always take from the bottom of the meniscus* 

Scientific Method

100

true/false:

Laws provide explanations for observations. 

FALSE 

THEORIES provide explanations for observations/laws. 

200

True/false 

A good hypothesis should have the potential to be wrong. 

True! A good hypothesis should have the potential to be proven wrong. 

300

"Matter is neither created nor destroyed" is an example of what:

A) Observations 

B) Laws

C) Theories 

B) Law 

400

Classify as an Observation, law, or theory:

When a metal is burned in a closed container, the mass of the container and its contents does not change. 

Observation 

*It is only describing what is happening in an experiment, not explaining nor defining*

500

Classify as an observation, law, or theory:
Matter is conserved in chemical reactions. 

Law 

* Law of conservation of mass, summarizes experiments that are consistent with his statement* 

Ball and Stick models

100

State the element: 

Red sphere 

Oxygen 

200

State the element: 

Black sphere 

Carbon 

300

State the element: 

White sphere

Hydrogen 

400

What color spheres/attachments will be in a carbon dioxide and water mixture? 

ex: 1 red sphere bonded to 3 white spheres. 

2 Red and 1 black sphere bonded together. 

2 white and 1 red sphere bonded together. 

500

Write the molecular formula given the ball and stick model. 

SEE GIVEN

CH₃COOH/ C₂H₄O₂