What is the molarity of a soln containing 0.5 mols NaOH in 5 L ?

Explanation:

1 mol NaOH = atomic mass of Na + atomic mass of O + atomic mass of H = 23 + 16 + 1 = 40g.

0.5 g NaOH = 0.5 / 40 mol NaOH = 0.0125 mol of NaOH

500 ml of water = 500/1000 = 0.5 L

Now, molarity = number of moles of solute / total volume of the solvent

= 0.0125 / 0.5 = 0.025 mol/L.

- lead + phosphoric acid = hydrogen + lead(ii) phosphate

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.