What is the molarity of a solution made by adding 1.565 moles of PbNO3 to 0.500L?

How do the energy differences between the higher energy levels of an atom compare with the energy difference between the lower energy level of the atom

Of the groups of elements below, which are most likely to gain electrons to become anions? a. alkali metal b. boron group c. halogen d. transition metal

What is the molar mass of a gas that has density of 2.054 g/l