Oct/Nov 2008 Q3, Why is it Aqueous lead (II) nitrate and not dilute sulfuric acid?
And also M/J 2009 Q26.
What does the fact that it's green has to do with anything?
Oct/Nov 2008 Q15, Why is it A (Decrease of 20) I did the calculations and I got 5?
Can anyone please help on those questions??
3)Lead Nitrate + Ba2+ + I- = Lead iodide + Barium nitrate. (soluble, thus will dissociate back into ions)
Lead iodide insoluble, yellow ppt. Barium nitrate, soluble.
with H2SO4, barium sulfate, insoluble, wont dissociate to ions, thus no Ba2+ ions...
26)Green - Iron salt
thus iron - high melting poinbt high density
15) Endothermic, so heat taken in. Decrease of 20 degrees. 5grams in 500cm^3 will take in more heat. U might have used direct proportion in ur calculations, its inversely proportional here...