Answer:
Dissolving sugar in water, burning paper, and melting gold are all chemical changes
Explanation:
The action cannot be reversed, or undone. Therefore it is a chemical change.
Boiling water is a physical change.
A. Water can dissolve a wide variety of substances
Answer:
electric charge
Explanation:
A nuclide is represented by the name of the element, preceded by the mass number (A) as a superscript on the left and the atomic number (Z) as subscript.
On the right, as a superscript is the electrical charge (e.g. +2) and is following the element name.
J.j Thomson electrons demo true indivisible sphere n Ernest central nucleas