# Weigh Out, Precipitate, and Electron Problems

40) A student wishes to repair 2.00 liters of 0.100 M KlO3 (molecular mass 214). The proper procedure is to weigh out:

a) 42.8 grams of KIO3 and add 2.00 kilograms of H2O

a) 42.8 grams of KIO3 and add H2O until the final homogeneous solution has the volume of 2.00 liters

b) 21.4 grams of KIO3 and add H2O until the final homogeneous solution has a volume of 2.00 liters

d) 42.8 grams of KIO3 and add 2.00 liters of H2O

e) 21.4 grams of KIO3 and add 2.00 liters of H2O

41) A 20.0 ml sample of 0.200 M K2CO3 solution is 30.0 ml of 0.400 M Ba(NO3)2 solution. Barium Carbonate precipitates. The Concentration of barium ions, Ba^2+, in solution after reaction is?

42) One of the outermost electrons in a strontium atom in the ground state can be described by which of the following sets of four quantum numbers

a) 5,2,0,1/2

b) 5,1,1,1/2

c) 5,1,0,1/2

d) 5,0,1,1/2

e) 5,0,0,1/2

https://brainmass.com/chemistry/modern-quantum-theory/weigh-out-precipitate-electron-problems-14997

#### Solution Preview

40)

2l of 0.1 M solution = 0.2 moles of solute in 2 lit of solvent.

Answer: d) 42.8 grams of ...

#### Solution Summary

40) 2l of 0.1 M solution = 0.2 moles of solute in 2 lit of solvent. 41) K_2 CO_3 + Ba(NO_3)_2 = Ba CO_3 + 2K NO_3.