What is the mass % of oxygen in lead (II)nitrate (Pb(NO₃)₂)rounded to three significant figures? A)4.83 B)19.3 C)29.0 D)14.5 E)0.331

Question

Quizplus · Accepted Answer

The molar mass of Pb(NO3)2 is:
Pb: 207.2 g/mol
N: 2 x 14.01g/mol = 28.02 g/mol
O: 6 x 16.00 g/mol = 96.00 g/mol
Therefore, the molar mass of Pb(NO3)2 is 331.22 g/mol.
The mass of oxygen in one mole of Pb(NO3)2 is 96.00 g.
The mass % of oxygen in Pb(NO3)2 is:
(96.00 g / 331.22 g) x 100% = 28.97%
Rounded to three significant figures, the answer is 29.0%. Therefore, the best choice is C.

What Is the Mass % of Oxygen in Lead (II)nitrate