Answer,
For example, silver ion can be precipitated with hydrochloric acid to yield solid silver chloride. Because many cations will not react with hydrochloric acid in this way, this simple reaction can be used to separate ions that form insoluble chlorides from those that do not.
They are used to make plane bodies.
Some are used for electrical wires eg copper because they are good conductors of electricity.
Used in building materials.
used to make jewelry eg gold and silver<span />
Answer:
If there's a grass area in the shape of a square and one side is 8 metres how much would it cost to fill the grass with fresh gravel at $5/metre
Answer: Option (3) is the correct answer.
Explanation:
A reaction due to which there occurs change in chemical composition of reactants is known as a chemical reaction.
For example, evolution of heat when two substances combine together shows a chemical reaction has taken place between the substances.
Whereas a reaction which does not bring any changes in chemical composition of the reactants is known as a physical reaction.
For example, boiling point, melting point, mass, volume etc are all physical properties.
Thus, we can conclude that out of the given options a substance melts when sitting in the Sun, is not an indication of a chemical reaction.
