question_answer

  How many (a) molecules (6) hydrogen atoms (c) oxygen atoms are there in 0.5 mol of water?

Answer:

                  (a) 1 mol of water contains 6.022 x 1023 molecules 0.5 mol ot water contains  molecules  = 3.011 x 1023 molecules (b) 1 molecule of water contains 2 atoms of hydrogen 1 mol of water contains 2 x 6.022 x 1023 atoms of hydrogen 0.5 mol of water contains atoms of hydrogen = 6.022 x 1023 atoms of hydrogen (c) 1 molecule of water contains 1 atom of oxygen 1 mol of water contains 6.022 x 1023 atoms of oxygen 0.5 mol of water contains atoms of oxygen = 3.011 X 1023 atoms of oxygen