what does it mean when we say that concentrated nitric acid has 16 molars
I've not heard the expression you list but I've heard something close to that. I've heard that concd HNO3 is 16 molar (written as 16M). What that means is that there are 16 moles of HNO3 in a liter of the solution. Since 1 mole HNO3 is 63 grams, 16 moles would be 16 x 63 = 1.008 kg/liter of the soln.
When we say that concentrated nitric acid has a concentration of 16 molar (16 M), it means that there are 16 moles of nitric acid dissolved in 1 liter of solution. This concentration is a measure of the amount of solute (nitric acid) present in a given volume of solvent (water).
To understand how this concentration is determined, we need to know the molar mass of nitric acid, which is the sum of the atomic masses of its constituent elements. Nitric acid (HNO3) consists of one hydrogen atom (H) with a molar mass of 1 gram/mole, one nitrogen atom (N) with a molar mass of 14 grams/mole, and three oxygen atoms (O), each with a molar mass of 16 grams/mole.
To calculate the molar mass of nitric acid, we add up these individual molar masses:
Molar mass of HNO3 = (1 gram/mole) + (14 grams/mole) + 3 x (16 grams/mole)
= 1 gram/mole + 14 grams/mole + 48 grams/mole
= 63 grams/mole
So, one mole of nitric acid weighs 63 grams.
If we have a concentration of 16 M, it means that there are 16 moles of nitric acid dissolved in 1 liter of solution. Since one mole of nitric acid weighs 63 grams, 16 moles would weigh:
Weight of 16 moles of nitric acid = 16 moles x 63 grams/mole
= 1008 grams
Therefore, in 1 liter of 16 M nitric acid solution, there are 1008 grams of nitric acid dissolved.