Chemistry Forum

As2O3

(C6H10O5)n
http://en.wikipedia.org/wiki/Dextrin

1) i would say A too 2) whats the question? 12) half life is 5715 so it will take 5715 years 13) I think its because positron has positive charge and electron has negative charge. So if you emit electron, you have lost 1 negative charge and nuclei has positive charge (more protones than electrones)....

ok:
1 litre of 22% acid means 220 ml of 100% acid and 780 ml of water.
the mass of the acid is 220*1.885 = 414.7 g
414.7g / 98g/mole = 4.23 moles of acid.

H3PO3 + 3NaHCO3 = Na3PO3 + 3H2CO3

we need 3 moles of NaHCO3 per 1 mole of acid i.e 12.7 moles

12.7*84.01g/mole = 1066.5 g of NaHCO3

H3PO3 + 3NaHCO3 = Na3PO3 + 3H2CO3 per mm of acid? dont you mean ml? It depends how concentrated is that acid so for example: for 81.9 g of 100% H3PO3 (1 mol) you need 3 * 84 = 252 g of NaHCO3 so if you tell me how much of the acid and how concentrated it is, I (or someone else) can tell you how much...

Ok, i asked today (if you still want the answer :p )
its simple:
by putting SO3 into the sulution of H2SO4 you can make even more than 100% H2SO4 ( the more SO3 in solution the more it will be like H2S2O7 I think) thats all i´ve got
hope I helpled you

hm if they say so.. if i dont forget, i will ask tommorow at school.
btw why dont you make AlH3 using different reaction?
like Al2Cl6 + 6LiH = 2AlH3 + 6 LiCl in ether enviroment

hi guys, can you please tell me how Mg3(BO3)2 and Co2B2O5 molecules looks like? I know that Co2B2O5 is linked together via oxygen atom and Mg3(BO3)2 is not but i cant figure out how exactly they look.
thanks

ok but still 98% H2SO4 is good enough for that.

Its Copper(II) hydrogensulfite if I am not mistaken

The formula depends on what crystal do you want. There are no general formulas how to make crystals.
If you want to make crystal, the easieast way IMO is to make a solution and then let the liquid part evaporate - by heating for eample.