Similar elements with similar properties were in the same groups and periods for instance lithium(Li) and sodium(Na) are alkaline metals and so belong to the same group (that is group 1).Also Hydrogen(H) and Helium(He) both have only one shell or energy level and so belong to the same period.
Answer:
A battery is a device that stores chemical energy and converts it to electrical energy. The chemical reactions in a battery involve the flow of electrons from one material (electrode) to another, through an external circuit. The flow of electrons provides an electric current that can be used to do work.
Answer:
percentage by volume of the solute = 45%
Explanation:
The percentage by volume of the solute in a solution is the percentage of the volume of the solute as against the overall volume of the solution.
In this example,
volume of solution = 300mL
volume of solute = 135mL
% volume of solute = (volume of solute ÷ volume of solution) × 100
= (135 ÷ 300) × 100
= 0.45 × 100 = 45%
∴ percentage by volume of the solute = 45%
Answer: a) 8.2 * 10^-8 N or 82 nN and b) is repulsive
Explanation: To solve this problem we have to use the Coulomb force for two point charged, it is given by:

Replacing the dat we obtain F=82 nN.
The force is repulsive because the points charged have the same sign.
Copper is the higher concentrated metal in this case.