My educated guess should be the 3rd one
Answer:
Copper(II) sulphate – sodium hydroxide reaction
The reaction between copper(Il) sulphate and sodium hydroxide solutions is a good place to start. If you slowly add one to the other while stirring, you will get a precipitate of copper(II) hydroxide, Cu(OH)2.
Answer:
So combining blue with yellow light is like combining blue light with red and green light. The result of combining these three primary colors of light is to produce white light.
Explanation:
