Answer: Formation of precipitate indicates that there has been a chemical reaction.
Explanation:
Chemical reaction: It is defined as change in arrangement of the atoms so as to form a new substance.
Mixing of two clear solutions that is lead nitrate and potassium iodide gives out yellow solid precipitate of lead iodide with aqueous solution of potassium nitrate.
The physical evidence which indicates that chemical reaction has been taken place is formation of yellow solid precipitate of lead iodide ,().
because they transfer an electron the sodium ion has a positive charge, and the chlorine ion has a negative charge so one gives off positive and one gives of negative