The % yield if 500 g of sulfur trioxide reacted with excess water to produce 575 g of sulfuric acid is calculated using the below formula
% yield = actual yield/ theoretical yield x100
actual yield =575 grams
to calculate theoretical yield
find the moles of SO3 used =mass/molar mass
= 500g/ 80 g/mol =6.25 moles
SO3+H2O=H2SO4
by use of mole ratio of SO3 : H2SO4 which is 1:1 the moles of H2SO4 is also= 6.25 moles
the theoretical yield of H2SO4 is therefore = moles /molar mass
= 6.25 x98= 612.5 grams
%yield is therefore= 575 g/612 g x100= 93.9 %
Answer:
A. 0.0655 mol/L.
B. PbBr2.
C. Pb2+(aq) + Br- --> PbBr2(s).
Explanation:
Balanced equation of the reaction:
Pb(NO3)2(aq) + 2NaBr(aq) --> PbBr2(s) + 2NaNO3(aq)
A.
Number of moles
PbBr2
Molar mass = 207 + (80*2)
= 367 g/mol.
Moles = mass/molar mass
= 3.006/367
= 0.00819 mol.
Since 2 moles of NaBr reacted to form 1 mole of PbBr2. Therefore, moles of NaBr = 2*0.00819
= 0.01638 moles of NaBr.
Since, the ionic equation is
NaBr(aq) --> Na+(aq) + Br-(aq)
Since 1 moles of NaBr dissociation in solution to give 1 mole of Br-
Therefore, molar concentration of Br-
= 0.0164/0.25 L
= 0.0655 mol/L.
B.
PbBr2
C.
Pb(NO3)2(aq)--> Pb2+(aq) + 2No3^2-(aq)
2NaBr(aq) --> 2Na+(aq) + 2Br-(aq)
Net ionic equation:
Pb2+(aq) + 2Br- --> PbBr2(s)
Answer:
B
Explanation:
The scientist had a wrong hypothesis?
1.8e-6 this should be the correct answer according to my mass converter.