question_answer

  (a) One mole of carbon atoms weighs 12 g. Find the mass of 1 atom of carbon in grams. (Avogadro's number = 6.022 x 1023per mole) (b) Calculate the mass of the following. (i) 0.5 mole of gas (ii) 0.2 mole of O atoms (iii) 4 moles of aluminium atom(Given N =14 u; 0 = 16 u; Al =27 u ;Avogadro's no. = 6.022x 1023 per mole)

Answer:

                       (a) 1 mole of carbon atom =6.022 x 10 atoms 6.022 x 1023 atoms of carbon weigh =12 g atom of carbon weighs (b) (i)n=0.5 mol ; M=14 x 2 = 28 g; w = ? m = n x M = 0.5x 28 = 14.0g (ii) n = 0.2 mol; M = 16 g; m = ? m = n x M = 0.2x 16 = 3.2 g (iii) n = 4 mol; M = 27 g; m = ? m = nx M = 4 x 27= 108 g