you need to make 1.5 liters of 0.5M CuSO4. How many mL of a 5.0 M stock solution would you need to make this

n has four pairs of electrons in the valence shell, electrons repel one another ,n has 7 protons in its nucleus, and since n has 7 protons, it must fill the second shell, giving it 4 pairs of electrons. the electrons form 3 bonds and 1 lone pair of electrons. each pair of electrons repels the other pairs, so they are equally far apart.

so all of the above

let that person have a turn to speak : )