The number of valence electrons of an element can be determined by the periodic table group (vertical column) in which the element is categorized
Answer:
A physical change, such as a state change or dissolving, does not create a new substance, but a chemical change does. In a chemical reaction, the atoms and molecules that interact with each other are called reactants. In a chemical reaction, the atoms and molecules produced by the reaction are called products.
Explanation:
When the student mixed the solution sodium carbonate with solution of copper(II) sulfate ; Copper Hydroxocarbonate , sodium sulfate and carbon dioxide gas was obtained as a products.
The balanced chemical reaction

Where:
= Copper(II) Hydroxocarbonate
= Sodium carbonate
= Copper(II) sulfate
= Sodium sulfate
= Carbon-dioxide
The conductance of the electric current through the electrolytic solution increases with increase in concentration.
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What is electrolytic solution?</h3>
Electrolytic solutions are solutions that are capable of conducting an electric current due to presence of ions.
The current flowing in an Electrolytic solutions is calculated as;
Q = It
I = Q/t
where;
Increase in the concentration of the charges, increases the amount of charges in the solution and hence the conductance of the solutions will increase as well.
Learn more about Electrolytic solutions here: brainly.com/question/14654936
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