Organic Chemistry Answers

The ion C6H5NH3+ behaves in a similar way to NH4+ because
A. Hydrolyze in water to give basic solutions
B. Neutralize acids to give salt and water
C. Ions are cations of strong bases
D. Hydrolyze in water to yield hydroxonium ions

A solution of CH3CO2Na in water is slightly basic because
A. It is a salt of a strong acid and a weak base
B. The salt dissociates to OH-
C. The salt dissociates to give Na+ which combines with OH- from water to give
NaOH
D. The salt dissociates to CH3CO2- which is hydrolyzed by water to produce OH-

Student X titrated 250cm3 of 0.1M with 0.1M HCl, using methyl orange as indicator. Student Y carried out the same exercise but used phenolphthalein as indicator which of the following statements about the titration is true?
a.the titre values obtained from the two titrations
b.the titre value of the titration by X is twice that by Y
c.the titre value of the titration by X is half that by Y
d.CO2 was released in the reactions in both titrations

3 a). Briefly explain the following terms:
Chirality
Achirality
Optical activity
Racemic mixture
Stereochemistry
3 b). i) Define the term hybridization.
ii) Differentiate between Enantiomers and DiastereoIsomers.
4 a). With a suitable example, show the type of hybridization in the following
classes of hydrocarbons:
Alkane
Alkene
Alkyne
4 b). An organic compound contains 47.3% Carbon, 10.59% Hydrogen and 42.11% Oxygen. Calculate
the empirical formula of the compound. If the vapour density of the compound is 22, find
the molecular formula of the compound.




6 a). Draw the structures of the following:
i. t- Butanol ii. Cyclohexane carbonyl chloride iii. 1-heptene
iv. Ethylethanoate v. cyclobutane carboxamide vi. cis-But-2-ene
vii. ethanedioic acid viii. Ethanamine

With a suitable example, show the type of hybridization in the following classe of hydrocarbon:
Alkane

When heated, calcium carbonate decomposed part of the substance. At the same time 4.48 liters of gas were released. The mass of the solid residue was 33.2 g. This residue was added to 300 g of hydrochloric acid, taken in excess. Determine the mass fraction of salt in the solution.

Mg(s) + O2(g) - MgO(s)

State whether this is a redox or metathesis reaction and indicate the reaction and the reason for your choice

Calculate the percentage yield of this reaction of 2MgO(s) if 0,15 moles of magnesium react with excess oxygen gas to form 5,4 grams of Magnesium oxide

A. An element with the valence electron configuration 2s2 2p5 would form a monatomic ion with a charge of_____ . In order to form this ion, the element will____ (lose/gain) _____electron(s) from/into the_____ subshell(s).

B. If an element with the valence configuration 4s2 3b6 loses 3 electron(s), these electron(s),would be removed from the ______subshell(s).

Give a reason Mercury iodide in red colour