Adding helium to a balloon increased its volume from 790.8 mL to 1.860 L. If the final number of moles of helium in the balloon is 15.3 mol, what was the initial number of moles of helium in the balloon

C. definite shape, definite volume. that is a solid.

Iam pretty sure that the answer is d

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.