jal prithvi par paya jane vala prakriti dvara pradatt ek taral padarth hai, jo sabhi praniyoan ke jivan ka bhautik adhar hai. isake bina prithvi par jivan ki kalpana nahian ki ja sakati. yah ek am rasayanik padarth hai, jisaka anu do haidrojan paramanu aur ek aauksijan paramanu se bana hota hai. vijnan mean jal ka rasayanik sootr 'H2O' hota hai.