. A sample of drinking water was found to be severely contaminated with chloroform '(CHCl_3)' supposed to he a carcinogen. The level of contamination was 15 ppm (by mass):i. express this in percent by mass ii. determine the molality of chloroform in the water sample.

A sample of drinking water was found to be severely contaminated with chorororm, 'CHCl_3', supposed to be carcinogenic in nature. The level of contamination was 15 ppm (by mass). i. Express this in percent by mass. ii..Determine the molality of chloroform in the water sample.

Examine the samples given. a) 20g He b) 44.8 L of NH_3 at STP c) 67.2 L N_2 at STP d) 1 mole of H_2 SO_4 e) 180g of water i) Arrange the samples in the increasing order of the number of molecules in each. ii) What will be the ascending order of the number of atoms? iii) What will be the mass of samples b,c, and d?

A welding fuel gas contains carbon and hydrogen only. Burning a small sample of î in oxygen gives 3.38 g carbon dioxide, 0.690 g of water and no other products. A volume of 10.0 L (measured at STP) of this welding gas is found to weigh 11.6 g. Calculate (i) empirical formula, (ii) molar mass of the gas, and (iii) molecular formula.