Chem Math Equation Thingys (1 Viewer)

[marcquelle]

ok can people post all relevant equations relating to the core and/or forensics. These are the only ones i know of:

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these are the only ones we have been taught at school. Are there any that i have missed?

 

[Divinity_]

c = n / v

v = n * mv

n = m / mm

delta H = - mcdeltaT

c1v1=c2v2

pH = - log (H+)

 

[marcquelle]

n = m / mm --> whats this one

v = n * mv --> and this one

C = n/v --> and this one

pH = -log(H+) ---> forgot that one

 

[mtsmahia]

C=n/v is the concentration formula u would of learned in prelim

 

[Divinity_]

n = m / mm --> whats this one

v = n * mv --> and this one

C = n/v --> and this one

pH = -log(H+) ---> forgot that one

n = m / mm

n = moles (mol)

m = mass (g)

mm = molar mass

v = n * mv

v = volume of gas (L)

n = moles (mol)

mv = molar volume (24.79L at 298.15K and 100kPa) or (22.71 at 273.15K and 100kPa)

c = n / v

c = concentration/molarity (molL^-1)

n = moles (mol)

v = volume (L)

pH = - log [H+/H30+]

[H+/H30+] = Concentration of Hydrogen/Hydronium ions. (molL^-1)

 

[iSplicer]

C = n/v --> and this one

pH = -log(H+) ---> forgot that one

You're gone.

 

[kaz1]

[H⁺][OH^-]= 1x10^-14

 

[adomad]

You're gone.

and he is ranked 3rd for chem at his school

 

[marcquelle]

yeah i know. But our teacher's method of teaching was to SUMMARISE HSC REVISE IN A MONTH. So not much help. I knew what the pH was but fogot to add it to the top cause its on the data sheet same as molar heat of combustion.

 

[adomad]

DW i was just joking around. im sure u will do fine in the HSC, just remember your formulas

 

[marcquelle]

dw. i got the highest mark in the trials and that wasn't even a pass 47 on the independant trial. 47 the highest not good in anyway

 

[saberbladexx]

dw. i got the highest mark in the trials and that wasn't even a pass 47 on the independant trial. 47 the highest not good in anyway

Whats your school rank?

 

[marcquelle]

i think like 503

 

[Schoey93]

i think like 503

'Like' is superfluous in that sentence. You do 4U English and you should know that.

503? Do you go to a TAFE college? I remember that you're about 20, so I guess you do, right?


Edit: LOL I hope I don't sound like a stalker...

 

[marcquelle]

no i go to a school. and i do know that but i;m not a member of the grammar nazis sorry, but i really have no idea. It sucks cause the schools old chem teacher retired then we got stuck with our new teacher who sucks royally.

 

[rips]

One very good one which isn't taught at schools but is often used chemistry lab is :

pH + pOH = 14.

so if yu need to know the pH of say 10mM NaOH, the pOH is neg log 1 x 10ex-2 = 2, so the pH must be 12.

Good luck out there in the HSC.

 

[emmcyclopedia]

One very good one which isn't taught at schools but is often used chemistry lab is :

pH + pOH = 14.

so if yu need to know the pH of say 10mM NaOH, the pOH is neg log 1 x 10ex-2 = 2, so the pH must be 12.

Good luck out there in the HSC.

^^^We were taught that one in class actually - so probably a good one to know =)

also:
Kw = [H+][OH-] = 1x (10^-14)

 

[gurmies]

^^^We were taught that one in class actually - so probably a good one to know =)

also:
Kw = [H+][OH-] = 1x (10^-14)

There is no difference between the two (mathematically).

 

[emmcyclopedia]

There is no difference between the two (mathematically).

true, it's just usually quicker to use Kw = [H+][OH-]
lol, saves you 1 whole line of working! =P