Inorganic Chemistry Answers

2. The pH of a 0.0516 M solution of nitrous acid, HNO2, is 2.34. What is its Ka?

1. What is the pH of a solution of HCl with a concentration of 1.2 X 10-3 M?

2. Calculate:

a. The rate constant for the radioactive disintegration of cobalt-60, an isotope used in

cancer therapy.

60Co27 decays with a half-life of 5.2 years to produce

60Ni28.

b. The fraction and the percentage of a sample of the 60Co27 isotope that will remain

after 15 years.

c. How long it takes for a sample of 60Co27 to disintegrate to the extent that only 2 % of

the original amount remains?

d. The half-life of 216Po84 is 0.16 s. How long does it take to reduce a sample of it to the

negligible amount of 0.000010 % of the original amount (1.0 x 10

-7

times the original

amount)?�

The reduction potential for Na (-2.71 V) is lower than that of the elements above it (Li, -3.04 V) and below it (K, -2.93 V). Explain the lack of a clear trend in the redox properties of the first 3 alkali metals. 

Aspirin (C9H8O4) in the form of a spherical tablet has a diameter of 0.04 inch. if the sample has a density of 1.4 g/cm3 How many carbon atoms does it contains?

1. Considering the following reaction: 3Si + 2n2 →Si3N4

2. When 26.8 moles of Si react with 21.845 moles of N2, how many moles of Si3N4 are formed?

3. What is the limiting reactant?

2. A 0.500 g sample of pure CaCO3 is dissolved in water to which 50.00 mL of HCl solution has been added. The solution then requires 6.20 mL of NaOH solution of which 1.000 mL = 1.010 mL of the HCl solution. What is the normality of each of the two solutions?

1. What is the normality of KOH solution if 45.18 mL are required to neutralize 0.300 g of pure oxalic acid (H2C2O4·2H2O)?

Automobile air bags are inflated by nitrogen gas generated by the rapid decomposition of sodium azide. If an air bag has a volume of 36 L and is to be filled with nitrogen gas at 1.15 atm and 26.0OC, how many grams of NaN3 must be decomposed?

NaN₃(s) = Na(s) + N₂(g)

How many grams of Al2O3 are formed from 15.0 L of O2 at 97.3 kPa & 21°C? 

Al + O₂ = Al₂O₃