Physical Chemistry Answers

My Benzyl Benzoate has gone from a liquid to a moist solid, I wondered what had caused this and if the secretions from the block could still be used for its original purpose as a Feather Mite 'a' cide

12. Answer ALL parts (a)-(e)

(a) What are hybridised atomic orbitals?

(b) What is the relationship between the number of atomic orbitals that
hybridise, and the number of hybrid orbitals formed?

(c) What angles are associated with orbitals in the following sets of hybrid
orbitals? (i) sp; (ii) sp3 Sketch both.

(d) Draw the Lewis structure of CH3CN. Indicate the hybrid orbitals and
draw a picture showing all the bonds between the atoms, labelling each
bond as σ or π.

(e) Can CH3CN function as a ligand? If your answer is “Yes”, explain how?

1. State the oxidation state of the central atom in the following species:
(a) SiBr4
(b) Cr(NH3)6Cl3
(c) NO3-
(d) PO4^3-

2. Balance the following oxidation-reduction reaction in acidic solution:
MnO4- + C2O4^2- >>>>>>>>>>>>> Mn2+ + CO2

3. In general, analogous bonds weaken down a periodic group, whereas for
dihalogen molecules, X2 we find the following bond strengths:
F-F 158; Cl-Cl 242; Br-Br 193; I-I 151 kJ mol-1

Comment on the reason for the normal trend and the exceptional value for
F2?

4. Draw all possible isomers of:
(a) [Co(NH3)3Cl3]
(b) [Ni(PMe3)(PEt3)Cl2]

1. What is the concentration of a solution in grams/Liter when 80 grams of sodium chloride, NaCl, is dissolved in 2 liters of solution?

Question 7 : The purest form of silicon dioxide is----
silicates
cristobalite
silibolite
rock crystal
Question 8 : The following are crystaline forms of silica, except------------
tridymite
quartz
cristobalite
Crystaamite
Question 9 : Which of the group V elements give only one oxidation state?
lead
bismouth
phosphorus
nitrogen
Question 10 : Which of the group V oxoacids is manufactured by Ostwald process?
dinitrogen tetraoxide
nitrous oxide
nitric acid
nitrogen hydroxide
Question 11 : Which of these is true of interstitial carbide?
they are non stoichiometric compound
they are soluble compounds
They are binary compounds
they are amorphous compounds
Question 12 : Which of the following is responsible for the easy hydrolysis of lead halides ?
availability of lone pair of electron in P orbital
completely filled d orbitals by electron
Availability of d-orbitals and low bond energy of Pb-H bond
availability of lone pair of electron in d orbital

Question 1 : When carbon is linked to elements of lower or approximately the same electronegativity,the binary compounds formed are termed
oxides
hydroxides
halides
carbides
Question 2 : Zeolites is used in water as----------
purifiers
disinfectants
softener
oxidants
Question 3 : Which of these is not a carbide?
dative
ionic
covalent
interstitial
Question 4 : One of these is not a form of silica
Flint
cristobalite
tridymite
Freons
Question 5 : The heavier elements of group IV functions as------
Lowry base
lewis base
Lowry acid
lewis acid
Question 6 : Which of these is not a raw material for the cement manufacture?
alumina
Silicate
lime
silica

Question 18 : Rusting of iron Is an example of________ reaction
Fast
Slow
explosive
Moderate

Question 19 : Which of the following statements about the kinetics of the reaction
H
2
(
g
)
+
B
r
2
(
g
)
→
2
H
B
r
(
g
)
H2(g)+Br2(g)→2HBr(g)
is definitely true?
The presence of hydrogen bromide, HBr, inhibits the rate of the reaction
The reaction is first order with respect to bromine, Br2.
It is not possible to determine anything about the kinetics of the reaction from the stoichiometry.
The reaction is second order overall.

Question 20 : Rate of reaction is defined as the
None of the above
Rate of change of conc. of product only
Rate of change of conc. of reactant only
Rate of change of concentration Of either reactant or product per unit time