If the reaction is represented by:
PCl₃ + Cl₂ <-> PCl₅ (exothermic)
the mole fraction of chlorine in the equilibrium mixture will change according to the following:
Decrease the volume: decrease
Increase the temperature: increase
Increase the volume: increase
Decrease the temperature: decrease
Answer
a) A solution with a hydronium molarity of 0.00045 is acidic. True
Doing the calculus of pH
![pH= -Log [H^{+}] = -Log (0.00045)](https://tex.z-dn.net/?f=pH%3D%20-Log%20%5BH%5E%7B%2B%7D%5D%20%3D%20-Log%20%280.00045%29)
b) pH is a way to express the hydronium concentration over a wide range. True
pH means –Log[H+] and this value is used to express a wide range of hydronium concentration sometimes obtaining pH minor than zero.
c) Percent K and Fe are determined by doing ion exchange then a pH titration. False
Usually, Fe is determined by redox titration with potassium permanganate due to it’s more accurate. On the other hand, K is determined usually by volumetric process which includes precipitation like potassium picrate precipitate
d) About 0.2M HCl is the reagent used for the pH titrations. False.
In order to do pH titration, it is possible to use a wide range of HCl concentrations and other acids as reagent if the analyte is a basic compound. Otherwise, if the analyte is an acid compound you should use a basic compound as reagent.
e) A Lewis base is specie that can donate a proton to an acid. False
A Lewis base is an electron pair donor.
1) Calcium carbonate contains 40.0% calcium by weight.
M(CaCO₃)=100.1 g/mol
M(Ca)=40.1 g/mol
w(Ca)=40.1/100.1=0.400 (40.0%)!
2) Mass fraction of this is excessive data.
3) The solution is:
m(Ca)=1.2 g
m(CaCO₃)=M(CaCO₃)*m(Ca)/M(Ca)
m(CaCO₃)=100.1g/mol*1.2g/40.1g/mol=3.0 g
5 plates is the highest amount that can be served
There’s only 5 sandwiches so 7 is automatically ruled out, there’s 14 corn cobs and 5 sandwiches only need 10 so it works out
In writing the formula for a salt the symbol of the cation is first then the anion is written second .