Physical Chemistry Answers

What is the value of density of mercury non si units?convert and express this quantity in si unit.

Calculate the number of charge of a metal which passes through a solution with 2.3A for 30minutes oand the mass of the metal is given to be 3.6g.

Molar m. =65gmol-¹

By considering the radial wavefunctions of the 2s and 3s orbitals of hydrogen, a) deduce the number of nodes for each, and b) their location(s).

Manganate ion MnO4- reacts with nitrogen IV oxide gas in an acid medium to give Mn2+ and NO3-. In the determination of NO2 (a pollutant) in a sample of air collected from an agrochemical industry, 10.5cm3 of 4.5 x 10-4 (or 0.00045M) of KMnO4 solution (in acid) was required for equivalence.
(a) Write down a balanced ionic equation for each half reaction above, hence the net ionic equation.
(b) calculate the number of moles of NO2 gas in the air sample
(c) calculate the number of NO2 molecules in the air sample
(d) What percentage of NO2 gas is present in 110.05g air sample collected
(e) Express the quantity of NO2 gas present in the air sample collected in
(i) ppm
(ii) microgram per metre cube

For the reaction: H2 (g) + I2 (g) <--> 2HI (g)
Keq= 50.0 at 448°C

How many moles of HI are present at equilibrium when 2.0 mol of H2 react with 1.0 mol of I2 in a 0.50L flask at 448°C?

a. NO2 + H2O →
b. BaCl2 + Na2SO4→
c. Al + Fe2O3 →
d. 2C4H6 + 11O2→
e. Ag + Pb3(PO4)2 →
f. HBr →
g. K2CO3 + CaI2

the standard enthalpy of combustion of ethane, carbon, and hydrogen are -1559.7 kJ/mol, -393kJ/mol and -286kJ/mol respectively.
Use Hess'ss law to find the enthalpy of formation of ethane

the standard enthalpy of combustion of ethane and hydrogen are -1559.7 kJ/mol and -286kJ/mol respectively, while the standard enthalpy of hydrogenation of ethyne to ethane is -296kJ/mol.
Use Hess'ss law to find the enthalpy of combustion of ethyne

Henrys Law constant for most gases decreases with increased temperature. Given that KH for O2 is 2.20 x 10-3 M atm-1 at 5oC, calculate the percent O2(aq) saturation if a lake water sample at 5oC and sea-level is found to contain, 9.20 mg/L of O2(aq). (Recall: partial pressure of O2 at sea-level = 0.2095 atm).

Henrys Law constant for most gases decreases with increased temperature. Given that KH for O2 is 2.20 x 10-3 M atm-1 at 5oC, calculate the percent O2(aq) saturation if a lake water sample at 5oC and sea-level is found to contain, 9.20 mg/L of O2(aq). (Recall: partial pressure of O2 at sea-level = 0.2095 atm).