What is the role of any scientist?
to explain the world around them
What is chemistry?
the study of matter and its properties, the changes that matter undergoes, and the energy associated with those charges
How do chemists study unobservable causes?
study observable changes in the universe
What effects how revolutionary something is?
The history of chemistry
What is the Scientific Method?
Observe Hypothesize Experiment Model Experiment back to top
What do we do since we can only observe the kind of small and not the really small?
make macroscopic observations and conclude on a microscopic scale
What is macroscopic?
things we observe with our eyes
What is microscopic?
cannot see but have significant evidence of
What are other names for microscopic?
Molecular
Particulate
What does symbolic mean in chemistry?
the ability of a chemist to convey a significant amount of information in a picture or symbol
What is an atom?
the smallest thing that retains properties that make up an element
What is a molecule?
atoms together
What is a compound?
2+ elements together
What is a mixture?
2+ substances physically intermingled
Only property that can be measured before, during, and after a change?
physical property
Property that can change in a chemical reaction and become different structure and substance?
chemical properties
What color is oxygen in a model?
red
What color is nitrogen in a model?
blue
How do you tell what element is what in a model?
color and size
What is intensive mean?
no matter how much you have of something, your results don’t change
What is extensive mean?
when the amount of something changes, its identity changes
Extensive or Intensive….Density
Intensive
Extensive or Intensive….Boiling Point
Intensive
Extensive or Intensive….Volume
Extensive
Extensive or Intensive….luster
Intensive
Extensive or Intensive….length
Extensive
Extensive or Intensive….charge
Extensive
Does intensive or extensive allow for comparisons?
Intensive
How do u get an intensive property with extensive ones?
two or more extensive properties
State of matter with strict limited movement?
solid
State of matter with some movement but still significantly contacting each other?
liquid
State of matter with free movement?
gas
State of matter with a lot of charge?
plasma
What is plasma?
partially ionized gas
What is the qualitative uncertainty in a measurement?
lacking confidence in the final digit you guess
What is the quantitative uncertainty in a measurement?
how we know how uncertain we are
How do u increase the certainty?
adding more significant figures
What is included in significant digits?
all the certain digits and 1 uncertain
What digits of equipment is uncertain?
the last digit
How many attempts do precise and accurate take?
precise = multiple attempts accurate = only need 1 attempt
What is precise and what is accurate?
precise = identical outcome every time accurate = getting the number you want
What are the two types of errror?
systematic
random
Which error can be corrected if caught?
systematic
Which error is found by using a comparison of the same instrument ?
systematic
Which error will always be too high or too low?
systematic
Which error varies and you need the average?
random
What does error do to certainty?
decreases certainty
increases uncertainty
What is consistent error, incorrect by a constant amount?
systematic
What is an error that exists in every measurement?
random
Method to express very small or large numbers allowing us to display sig figs?
scientific notation
Sig Figs: 0.30 0.0054 3.70 800 800.
2 2 3 1 3
What numbers in scientific notation are sig figs?
all of them
Your confidence is a calculation is only as good as your _____?
worst measurement
Sig Figs for addition and subtraction?
least number of decimals = decimals in answer
Sig Figs for multiplying and dividing?
the least number of sig figs = sig figs in the answer
What do you do when you round with a 5?
round up
on what tools is very digit significant?
printed tolerance
error
What is an exact number?
a number with no uncertainty
How many sig figs does an exact number have?
infinite
When do we consider sig figs in the conversions?
metric to us
what is the system called where u convert with factors of 10 and its based on prefixes?
SI units
metric to metric conversions