Let's say for example I have 5g of copper in a beaker. Mass would be 5g + mass of beaker. If I add any given amount of water to the beaker containing the copper, that will change the mass of the beaker containing the copper. Am I correct so far? So then if I pour out the water, but keep all the solid copper inside the beaker, the copper is still wet. So I leave the beaker containing the copper to dry overnight, the water "vaporizes" and then do I now have the original mass of 5g of copper + mass of beaker?
Yes as long as the copper you left wet doesn't oxidize or otherwise react with something OR if the wet stuff left is not pure H2O. Water from the faucet usually contains Ca and Mg salts and when the liquid evaporates it leaves a very small residue in a beaker. It isn't much but it's enough to weigh. But as long as everything is pure and no other reactions occur you are right.
Yes, you are correct so far. When you have 5g of copper in a beaker, the total mass would be 5g plus the mass of the beaker itself. If you add any amount of water to the beaker containing the copper, the mass of the beaker and copper will increase due to the added mass of the water.
However, when you pour out the water while keeping the solid copper inside the beaker, it's important to note that the copper itself does not become wet. Wetness is a property of substances that are in contact with a liquid, but the copper remains a solid and does not absorb the water.
When you leave the beaker containing the copper to dry overnight, the water molecules on the surface of the copper will evaporate. This means that the water changes from a liquid state to a gaseous state and escapes into the surrounding air. As the water vaporizes, the mass of the beaker and copper will decrease slightly because some of the water is leaving the system.
However, it's important to consider that there may still be some water trapped within the pores or surface imperfections of the copper, which may not completely evaporate overnight. To ensure that all the water evaporates, it is best to heat the beaker gently to accelerate the evaporation process.
Once all the water has evaporated, you should have the original mass of the copper (5g) plus the mass of the beaker, as the water has been removed from the system.