A student forgot to add the reaction mixture to the round bottomed flask at `27@`C but put it on the flame.After a lapse of time,he realised his mistake.By using a pyrometer,he found that the temperature of the flame was `477^@C`. What fraction of air would have been expelled out?(2+3)

An electric toaster uses nichrome for its heating element. When a negllgibly small current pases through it, its resistance at room temperature (27.0^(@)C) is found to be 75.3 Omega. When the toaster is connected to a 230 V supply, the current settles, after a few seconds, to a steady value of 2.68A. What is the steady temperature of the nichrome element ? The temperature coefficient of resistance of nichrome averaged over the temperature range involved is 1.70 xx 10 ^(-4)"" ^(@)C ^(-1).