Answer:
0.294 M
Explanation:
The computation of the final molarity of acetate anion is shown below:-
Lead acetate = Pb(OAc)2
Lead acetate involves two acetate ion.
14.3 gm lead acetate = Mass ÷ Molar mass
= 14.3 g ÷ 325.29 g/mol
= 0.044 mole
Volume of solution = 300 ml.
then
Molarity of lead is
= 0.044 × 1,000 ÷ 300
= 0.147 M
Therefore the molarity of acetate anion is
= 2 × 0.147
= 0.294 M
The molar mass is the mass of a given chemical element or chemical compound (g) divided by the amount of substance (mol). The molar mass of a compound can be calculated by adding the standard atomic masses (in g/mol) of the constituent atoms.
Answer:
18.52g
Explanation:
(relative atomic masses: H = 1.01, O = 16.00, Ca = 40.08)
Equation (balanced):
Ca + 2H2O -> Ca(OH)2 +H2
First, calculate the number of moles of 10g calcium
No. of moles of Ca = 10/40.08 = 0.25 mol
Then, calculate the number of moles of 20g water
No of moles of H2O = 1.11 mol
According to the balanced equation, 1 mole of calcium reacts with 2 moles of H2O completely. Therefore, H2O is in excess.
So, 1 mole of calcium reacts with water to form 1 mole of Ca(OH)2 (according to the mole ratio shown in the balanced equation)
Therefore, 0.25 mol of Ca(OH)2 is produced.
Mass of Ca(OH)2 produced = no. of moles x molar mass = 0.25 x (40.08 + 16 + 16 + 1.01 + 1.01) = 18.52g
Good luck!