Find the molarity of iodide ions in a solution obtained by dissolving 1.97 g of ZnI2(s) and enough water to form 34.2 mL of solution. Assume complete dissociation of ZnI2(aq) into ions. The molar mass of ZnI2 is 319.22 g/mol. Give the answer in mol/L with 3 or more significant figures.

The molarity of iodide ions in given solution is 0.181 M.

Explanation:

Given: Mass = 1.97 g

Volume = 34.2 mL (1 mL = 0.001 L) = 0.0342 L

Molar mass of = 319.22 g/mol

Moles is the mass of substance divided by its molar mass. Hence, moles of are calculated as follows.

Molarity is the number of moles of a substance present in liter of a solution.

So, molarity of given solution is calculated as follows.

Thus, we can conclude that molarity of iodide ions in given solution is 0.181 M.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.