guess what? UNIT 4(?) test Flashcards
what is an equivalence point?
when the H+ ions = OH- ions
is the equivalance point always at pH = 7?
nope
what equation do you use for titration stoich?
STEP 1. CONVERT VOLUME TO L
Cknown –xVknown–>nknown–mole ratio–>nunknown–/Vunknown–>Cunknown (but now it is known. funny how that works.)
how to find pH on calculator. actually, these will probs be given, dont zero in on this.
pH = - log^[h+]
how to find h+ ions on calc?
10^[-pH]
how is strength measured through the pH scale? ie from 1 to 2 compared to 1 to 3
every number is 10X stronger than the one before it. H+ ions in something pH 1 = 0.1.
H+ has the same amount of 0 as there are numbers in the pH scale. like 3 has 3 zeros, 0.001. its pretty nifty.
how do you do solution stoich?
- convert volume to liters. (this step is very important)
- divide mass by known concentration
- can we get a ‘What! what!’ for a MOLE RATIO
- c=n/v
what do chemists do in plays?
they actinium
what is solubility?
the amount of solute that will dissolve in a given amount of solute at a given temperature.
when a solute dissolves in a solvent, what is true abt their attractions?
the solute attractions are less than that of the solvent.
how does taste change from acid to base
acids are sour bases are bitter
how does feel change from acid to base
acids have no characteristic feel, bases are slippery
how does the colour of phenothalein change from acid to base
acids are colourless, bases are magenta
how does conductivity change from acid to base
it doesnt change, both are conductive
how does metal reactivity change from acids to bases?
it doesnt change, both react with metal.
ni=nf, therefore…
CiVi=CfVf
true or fasle: bases are proton donors
whoopsie its false ur thinking about acids u dummy. bases are proton receptors.
hydrogen bonding
its FON! hydrogen bonds form when hydrogen bonds to flourine, oxygen, and nitrogen… also makes dissolving harder, not fon.
solubility in covalent compounds
polar molecules dissolve in polar solvents and vice versa.
solubility in ionic compounds
for an ionic substance to dissolve, water must have stronger attractions to ions than htey have to themselves.
what are factors that affect solubility?
- size, smaller molecles dissolve easier
- temp, higher temp makes more energy to help break attractions
- pressure, increaseing pressure in gas solutes increases solubility because gas is forced into solution
what is concentration?
what is a part per million?
amount of stuff / unit of space
the same as 1 mg in 1 L
basic formula for concentratiomn
1) % to g
2) grams divided by 100 and sometimes multiplied by volume
3) answer?
were going to have to just wing it. jk do the practice questions.
where do german chemists wash their dishes?
in de zinc