Total number of electrons present in 1.8 grams of water is (a) 6.023x10^22 (b) 6.023x10^24 (c) 18x10^23 (d) 6.023x10^23

1 mole of water = 18 grams (you can find this by finding mass of two hydrogen and one oxygen which is (1*2) + 16 = 18)

1.8 grams = 0.1 moles

1 H2O molecule has 10 electrons so  0.1 moles can be computed as:

(6.023*10^23)*(0.1)*10 = 6.023*10^23 electrons

14 days is the half-life of phosphorus-32