People have thought that everything had went around the earth Our understanding of the universe has changed over time. Different civilizations have created different models to explain what the universe
is and how the universe began. The Greek astronomer Ptolemy
used measurements of the sky to create his geocentric model. This had the earth at the center and all the planets and the sun orbiting around it.
The correct answer for this question is letter C. Newland's Law of Octaves was rejected mainly because it could not hold good for elements heavier than calcium. The relationship between the octaves started to break down since it was unable to accommodate newly discovered elements.
Answer:
Explanation:
HF ,Hydrofluoric acid happens to be a weak acid and as we know that a weak acid is partially dissociated in water.
So when we dissolve HF in water it would subsequently dissociate into H⁺ and F⁻ions . The solution now would contain hydronium ion that is H+ ion.
The solution would also contain dissociated F⁻ ion and solvent H20 molecules.
The following reaction would take place:
HF+H₂O⇆H₃O⁺+F⁻
so the reaction in forward direction is the dissociation of HF into H₃O⁺(that is H⁺) and F⁻ion.
The backward reaction would be the recombination of H₃O⁺(that is H⁺) and F⁻ion to give back HF and H₂O