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Repost from N/a
SALTS
titration : both reactants are aqueous
1) pipette known vol of HCl into conical flask w phenolphthalein
2) HCl titrated with NaOH solution in the burette, stop when pink appears
3) repeat the experiment with known volume of HCl and NaOH w/o indicator (pure salt)
3) transfer to evaporating dish and heat until saturated, allow to cool
adding excess solid : one of the reactants are insoluble base/carbonate
1) add excess CuO to a known volume of dilute H2SO4 solution, stir
2) filter CuSO4 solution to removes excess CuO
3) transfer the solution to an evaporating dish and heat until saturated, allow to cool
precipitation: reactants aqueous, salt produced insoluble (my father washes dishes)
1) mix and stir, filter, wash and pat dry with filter paper
Repost from N/a
metals w cold water - metal hydroxide and hydrogen gas (up to Mg)
metals w steam - metal oxide and hydrogen gas (up to Fe)
Repost from N/a
ORGANIC CHEM
alkane : CnH2n+2
> substitution, UV light, (di/tri)chloromethane and HCl
alkene : CnH2n
> hydrogenation, nickel, 180°c, (veg oil to margarine)
> bromination, dibromoethane
> addition polymerisation, 100 atm, 200°c, plastic products
> produced by cracking, 600°c, Al2O3/SiO2 (porcelain chips)
alcohol : CnH2n+1OH
> fermentation, 40°c, 15%
> oxidation
carboxylic acids : CnH2n-1COOH
Repost from N/a
AIR !
- nitrogen 78%, O2 21%, argon is the most abundant noble gas
- pollutants : unwanted substances which are harmful for living things and the environment
- CO : incomplete combustion
- SO2 : volcanic activity, combustion of fossil fuels w sulfur
- NO, NO2 : car engines, high temp, lightning activity
- CH4 : decay of dead organic matter
- acid rain pH 4-5
- test for sulfur dioxide in air with acidified potassium manganate
how was the paper ?! that light intensity qn was so confusing bcs of the units, i didn't finish it 🥲
anyways , time to grind for math 💪 ! ive heard alot of people worrying about the bellcurve and moderation for math but lets focus on what we can control okay , we can spend our time rn focusing and last min studying , and thats all we can do for now ~
desperate call for help 🙏 any tips for geo P1, im aiming for a1 but cant get anyth into my head HAHAHA
i never would have thought the the first yearly tys i alm finished is chem 💀 im so proud of myself for coming so far and finally understanding chem, sure i used to get decent grades but that was just memorisation and physics pulling me up, but now chem is my best science 😭
sorry for the lack of updates , q doomed for o’s HAHA but i’ll tell uall my plan for the rest of o’s here 😭
Repost from study with hillary
NA topical science (biology & chemistry)
— one book for $7.95! (original price)
pm @hjllary if interested :-)
my ypt timings have been looking better recently but i think i can do better
sorry for the lack of updates i totally did not forget abt this channel
