hallowedredemption

hydrogen bromide dissociates when heated according to the equation

2HBr <---------> H2+Br2

initially 0.25 moles of HBr is placed into a 1dm3 reaction vessel.

when the reaction comes to equilibrium, the concentration of h2 is found to be 0.05M calculate the equilibrium constant ..

i think kc = [H2][Br2]

________

[2HBr]

kc= [0.05][Br2]

___________

[0.125]

from here on i get confused ..

phosphorus pentachloride reacts with water to give phosphoric acid and hydrogen chloride according to the following reaction

PCL5 +4H2O -------> H3PO4+5Hcl

in an experiment , 0.360 mol of PCL5 was added to 2.88 mol of water.

1 determine the limiting reagent

2 what is the theoretical yield ?

also The exact neutralistaion of 20.00 cm3 of 0.05M sulphuric acid (H2SO4) requires 35.65 cm3 of sodium hydroxide solution. calculate the molarity of the sodium hydroxide ..

! draw the cis and trans isomers of 3-hexene

i understand the principles of these isomers just cant figure out how to draw them ..

also show how the double bond in alkenes is made up of sigma and pi bonds

ch3ch2ch2oh h3PO4

-----------> ?

ch3ch2ch2cho+HCN --------> ?

ch3ch2ch2cooh+NH4OH---->?

ch3chohch3 KMnO4

-----------> ?

ch3ch2cooh+ch3ch2oh h+

-----> ?

please any help at all with this im at my whits end with this ... need it badly for friday ... x