quiz 1 Flashcards
scientific notation, significant figures, common lab equipment,
stout glass cylinder with a beak
beaker
stereotypical “science” flask, cone-shaped bottom with cylindrical top
erlenmeyer flask
long scoop with a pointed end, usually metal
scoopula
tall, narrow cylinder with beak
graduated cylinder
safety-pin like end with tongs that cross to fit shape of test tube
test tube holder
container with top
crucible
tongs with slots for fingers at top, tongs cross with seagull-shaped waves
crucible tongs
stand for placing something on with clamp that provides additional surface
stand and ring clamp
basically tweezers
forceps
dropper with squeezable top
dropper pipet
most fucked up looking clamp, the part that attaches to the stand has a c shape w a screw going thru and then test tube shaped tongs on the other end
utility clamp
key-shape (smooth edges) with barbell attached to it
pinch clamp
symmetrical clamp meant to hold a tube in its center
buret clamp
deep bowl-shaped glass
evaporating dish
shallow bowl-shaped glass, like a contact
watch glass
long rubber or plastic scraper
rubber policeman
dec places/sig figs in calculations
for add/sub, take the lowest # of DP in the equation and round the answer to have that # of DP
for mult/div, take the lowest # of SF in the equation and round the answer to have that # of SF
when solving complex equations with sig figs/dec places
use the extra sig figs/dec places and only consider their intended sig fig/dec place in the end
what is a significant figure
nonzero digits, interior zeroes, trailing zeroes to the right of a decimal (ex 4.0)
what isn’t a significant figure
leading zeroes (to the left of a first nonzero digit, ex the “.00” in “.004”), trailing zeroes before an implied decimal point (ex the “00” in 1200)
number of dec places you must report when measuring…
1/10 of the smallest marked increment of measurement, AKA one digit further to the right
ex: if the smallest increment is 1 mL, you report to the 0.1 mL
order of magnitude
the exponent in scientific notation.
ex: 10^3 has OoM of 3, so two notations that both have 10^3 have the same OoM. 10^3 and 10^5 have a difference of 2 OoM
scientific notation
A digit (probably followed by a decimal point and some other digits, depending on the req # of sig figs) x 10-to-a-power. ex: 4 x 10^0 (=4), 9.6 x 10^1 (=96), 3.045 x 10^2 (=304.5), 2.1 x 10^(-1) (=.21)
to find/calculate sci notation,
when 10^a, move the decimal “a” digits to the right.
when 10^(-a), move the decimal “a” digits to the left.
laws vs theories
a law is a brief statement that summarizes past observations and predicts future ones, while a theory is a broader, deeper explanation for observations and laws. it is a model of the way nature is and often predicts behavior that extends beyond observations and laws
observations
measurement of some aspect of nature.
scientific method
a self-correcting process composed of observation, hypotheses, testing hypotheses with an experiment, and formulating laws and theories
hypothesis
tentative interpretation or explanation of observations. a good one is falsifiable, meaning it is able to be proven wrong
experiment
a highly controlled observation designed to validate or invalidate a hypothesis
wire triangle with clay on it
clay triangle
screen of wire
wire screen