Un átomo tiene 5 electrones de valencia en el 4to nivel y 40 neutrones. Determine el número de masa.

How many grams of magnesium metal will react completely with 8.3 liters of 5.5m hcl? show all work

What’s the theoretical yield of solid lead

Suppose that some of the compound spilled out of the crucible after it was heated. would that cause the percent by mass of water in the compound determined by the experiment to be too low, too high, or unchanged? briefly explain your answer.