Which of the following was originally a tenet of dalton's atomic theory, but had to be revised about a century ago?
atoms are tiny indivisible particles.
the atoms of any one element are different from those of any other element.
compounds are made by combining atoms.
atoms of different elements can combine with one another in simple whole number ratios.

According to arrhenius theory of acid and bases, an acid is a proton donor, while base donates hydroxyl ions. further, acid and base reacts to form salt and water.consider following example.hcl    +      h2o          →      cl-          +      h3o+here, hcl has donated a proton, hence it is an acid.now consider following reactionhcl      +      naoh            ↔      nacl      +        h2oin this reaction, hcl donates proton, hence it is acid. on other hand, naoh donates hydroxyl ion (i.e. hence it is a base.