Explain what happens at the atomic level to cause the colors to be seen?

Astudent carefully transfers 30 g of water and 30 g of alcohol in a glass tube, forming two layers and filling the tube completely. after sealing the tube, the student mixes the solutions, and notices a bubble that forms in the tube. what is the mass of the contents in the glass tube after mixing?

What material does not melt at any temperature

How does the motion of particles in a gas change as the gas cools