1. An English Physicist Rayleigh performed a series of experiments to determine with great accuracy, how much a litre of N2 weighs (eg. its density)
So he proceeded to remove the O2, CO2 and water vapour from air to get pure N2 before weighing it.
To check his results he used another method to obtain N2 instead of from air. He extracted N2 from ammonia, and purified it according to all the rules and weighed it. A litre of N2 from air weighted 1.2572g while that from ammonia weighed 1.2560g.
Suggest an explanation why the N2 from air was heavier than the N2 obtained from NH3.(assuming it was not due to experimental error)
2. A student made crystals of sodium sulphate from NaOH and dilte H2SO4 from the following procedures.
Some NaOH solution was placed in an evaporating dish and a few drops of litmus solution added. The dilte H2SO4 was then added slowly from a measuring cylinder until the litmus solution changed colour. The solution in the evaporating dish was then heated strongled untill all the water has evaporated.
State the colour change of litmus solution (the same as litmus paper???)
If yes then my guess is from blue to red. Hahah!
;D
Noble gases.