CHEM 120: Lab Final
35 Cards in this Set
| Front | Back |
|---|---|
|
what color are cobalt solutions usually?
|
blue/rose
|
|
how does acidity of a solution affect the color of blue litmus paper?
|
acidic=red, basic solution=stays blue
|
|
difference between nonluminous/luminous flame (which is most commonly used in labs)
|
nonluminous=natural gas (mixture of hydrocarbons, mostly methane) with enough oxygen to produce a blue flame, producing CO2 and H2O as combustion products. 2 cones. most commonly used in labs.
luminous=natural gas with insufficient supply of oxygen, producing a yellow flame. combusion pr…
|
|
what are clay triangles used for in labs?
|
to hold crucibles over a flame.
|
|
what is used to detect the presence of starch?
|
what is used to detect the presence of starch?
|
|
name products and reactants involved in producing aspirin.
|
salicylic acid and acetic anhydride=reactants
aspirin/acetic acid=products.
|
|
write equation made by Dulong and Petit describing heat capacity for metals
|
c=3R/m
|
|
what are centrifuges/supernatants?
|
centrifuge=high speed machine used to seperate a solid out from a liquid solution.
supernatant=liquid part on top of the centrifuged solution.
|
|
write molecular/ionic/net ionic equation of sodium carbonate and hydrochloric acid
|
Na2CO3+HCl--2NaCl+CO2+H2O....ionic=all elements, net ionic=only ones that matter/not spectator ions.
|
|
how does one check for qualitative purity?
|
check melting point
|
|
what types of ions compose an alum?
|
sulfate ion, water, a univalent and trivalent cation.
|
|
what was the limiting reagent in the potassium alum experiment?
|
aluminum
|
|
common unit of density
|
g/mL
|
|
big rule for sig figs
|
add/sub=number w/ least decimal place
mul/div=number w/ least number of sig figs
|
|
absolute zero (celcius and kelvin)
|
-273.15 celcius
-0 kelvin
|
|
what is the meniscus
|
the curve of a liquid close to the surface of a container, due to surface tension.
|
|
write formula for potassium alum
|
KAl(SO4)2*12H2O
|
|
draw mental picture of flame/label areas
|
outside cone=blue flame, middle inside=hottest part of flame, below middle inside=-bright blue flame
|
|
intensive properties (+ ejemplo)
|
properties independent of sample size. density
|
|
describe two valves on bunsen burner/what each control
|
bottom valve=gas (big v small)
higher valve=air (cool v hot)
|
|
big characteristic of epsom salt/chemical formula/describe before and after in experiment
|
6 or 7 water molecules, depending on appearance.
MgSO4*7H2O
crystals-->powder
|
|
define 4 characteristics of chemical reaction
|
gas evolved, precipitate formed, heat evolves, color change occurs.
|
|
sodium chloride (how it reacts w/ AgNO3, NaOH, HCl)
|
precipitate, nr, nr
|
|
sodium carbonate (how it reacts with AgNO3,NaOH, HCl)
|
precipitate, nr, gas
|
|
magnesium sulfate (how it reacts with AgNO3, NaOH, HCl)
|
nr, cloud/color, nr
|
|
ammonium chloride (how it reacts with AgNO3, NaOH, HCl)
|
precipitate, gas, nr
|
|
water (how it reacts with AgNO3, NaOH, HCl)
|
nr-->
|
|
how to find empirical formula
|
calculate moles of each product being used, then find mole to mole ratio of substances to find approximate emp. formula.
|
|
name colors for each of the 3 halogens in experiment 11
|
chlorine=yellow
bromine=orange/brown color
iodine=dark purple color
|
|
give difference between gravity/vacuum filtration
|
gravity=simple filter/filter paper.
vacuum=tube to sink/sink all the way on.
|
|
rewrite ideal gas law, including molar mass and mass in grams
|
PV=gRT/M
|
|
color of copper
|
reddish
|
|
color of iron
|
silver
|
|
color of nickel
|
silvery white
|
|
4 equations to copper cycle
|
Cu+4HNO3-->Cu(NO3)2+2NO2+2H2O
Cu(NO3)2+2NaOH-->Cu(OH)2+2NaNO3
Cu(OH)2+H2SO4-->CuSO4+2H2O
CuSO4+Zn(Al)-->ZnSO4+Cu
|
CHEM 120: Lab Final