It is seen that in first and third ones elements are not changed but only their chemical arrangements are changed. both are chemical reactions.
In the second and last one elements are changed after the reaction and as we know non chemical reactions are not capable of doing that so they are nuclear reactions.
There are other ways to tell like checking number of neutrons as well but in this simple case I don't think it is necessary to check those.
Good luck!
Answer:
They are fossil fuels because they were formed because of fossilized remains of animals and plants that lived many years ago. They also have a high carbon content.
Answer:
As with the hydrogen-ion concentration, the concentration of the hydroxide ion can be expressed logarithmically by the pOH. The pOH of a solution is the negative logarithm of the hydroxide-ion concentration. pOH=−log[OH−] The pH of a solution can be related to the pOH.
149 g of cobalt are present in 1.52 x atoms of cobalt.
<u>Explanation</u>:
One mole of an atom is equal to the Avagadro number of the atom.
The number of atoms per mol is divided by the given atoms of Cobalt.
=
= 2.52 mol of Co
To covert, the moles into grams multiply the mole value by its molar mass
The Molar mass of Cobalt is 58.93
= 2.52 58.93
= 149 g.