General Chemistry Answers

Nitrogen gas, N_{2} can be prepared by passing gaseous ammonia over solid copper(II) oxide, CuO, at high temperature. The other products of the reaction are solid copper, Cu, and water vapor.

2NH3 (g) + 3CuO (s) → → N₂ (g) + 3Cu (s) + 3H₂O(g)

In a certain experiment, a reaction mixture containing 100.0 g CuO and excess amount of ammonia, NH 3 , yields 7.46 g N_{2} What is the percent yield for this experiment?

Calculate the wavelength of A muon (a subatomic particle with a mass of 1.884 ×

× 10^–25 g) traveling at 695 m/s:

An equation to show the enthalpy change for a strong and strong base which is -57.3kj

10.567 g sample of HCl required 75.45 ml of 0.9785 M of Sodium Hydroxide in titration,compute for percent purity

Directions. Solve the following problems. Show your solutions.

I. For the voltaic cell, 2 Na(s) + Fe2+(aq) → 2 Na+

(aq) + Fe(s)

a) Write the two half-reactions.

b) Write the cell notation.

c) Calculate E ° for the cell.

II. Consider the fission reaction 1

0n + 235

92U →

89

37Rb + 3 0

-1e + 3 1

0n + 144

58Ce

How much energy in kilojoules is released per gram of Uranium- 235?

III. For Al-28, calculate the binding energy in kilojoules /mol?

IV. Sketch a portion of the acrylonitrile polymer ( Refer to Table 23.1) assuming it is a

a) head-to-tail polymer

b) head-to-tail, tail-to-tail polymer

What is the empirical formula for the molecule?

 A Molecule has been identified that contains three elements: carbon, hydrogen and oxygen.  When the molecule is broken down, the mass percentages are:

C= 40.9%

H= 4.58%               

O= 54.5%

The percentage of the x-21 isotope is 87.99% what is the contribution to the weight average from the x-21 isotope which has a mass of 21.00 amu

c) One pack of chips weighing 140 g contains 2.5% salt. Decide if Barborka was right that by eating two such packs of chips, the 65-kilogram Samo would exceed the recommended daily dose of salt.  (The recommended daily dose is 100 mg per 1 kg body weight)

Potassium iodate is most often used to iodide table salt. The weight fraction of potassium iodate in table salt is 0.006%. 0.59 g of iodine is contained in 1.00 g of potassium iodate. 

e) Calculate how much g of salt Samo needs to eat to cover his daily iodine requirement. Assume that Samo does not receive iodine from other sources, only through iodized table salt.

Given the following volumes of gases at 54.0°C and 790 torr, calculate the number of moles and the mass of a 150.0 mL Xenon gas