Discussion:
Buffer Solution and Entropy
1-A 1.0-L buffer solution is 0.105M in HNO2 and 0.145M in NaNO2. Determine the concentrations of HNO2 and NaNO2 after addition of 1.4g NaOH .Express your answers using three significant figures separated by a comma.
2- A 1.0-L buffer solution is 0.105M in HNO2 and 0.145M in NaNO2. Determine the concentrations of HNO2 and NaNO2 after addition of 1.4g HI. Express your answers using three significant figures separated by a comma.
3- Which processes are nonspontaneous?
a bike going up a hill
a meteor falling to Earth
obtaining hydrogen gas from liquid water
a ball rolling down a hill
4-predict the sign of ΔS sys for each chemical reaction. ΔS sys >0 or ΔS sys <0
2KMnO4 (s)→K2MnO4 (s)+MnO2 (s)+O2 (g)
CH2 =CH2 (g)+H2 (g)→CH3 CH3 (g)
Na(s)+1/2Cl2 (g)→NaCl(s)
N2 (g)+3H2 (g)→2NH3 (g)
5-Why does a gas have greater entropy than the corresponding solid? Choose from:
The entropy change of sublimation (solid going directly to gas) is positive.
There are more available types of kinetic energy in a gas. In a solid, the molecules can only vibrate.
A gas expands to fill its container, while a solid maintains a constant shape.
Particles in a solid move slower than in a gas.