a. Define thefolfowing terms
i. Atomic Number
ii. Mass Number
iii. Isotope ( 3 mks )
b. An alkane has a vapour density of 8 . Determine the following
i. Molecular formular
ii. Structural formula ( 14 mks )
State three progerties of protion (3 mks)
QUESTION 2
ar Write the electronic configuration for the following elements using orbital method
i. 26 Fe
ii. 24 Cr
iii. \( { }_{29} \mathrm{Cu} \)
iv. 30 Zn
( 8 mks )
State three derefeiences between s-orbital and p-orbital ( 6 mks )
er Calculate the percentage by mass of nitrogen in ammonia trioxonitrate \( (\mathrm{V}) \) salt ( \( \mathrm{NH}_{4} \mathrm{NO} \)
\[
(\mathrm{N}=14, \mathrm{H}=\mathrm{b}, \mathrm{O}=16) \quad(6 \mathrm{mks})
\]
QUESTION 3
a. List five scientists whose work led to the development of the periodic table ( 5 mks )
b. Calculate the volume of oxygen liberated at STP when a current of 2.5 A is passed throu of copper salt. \( \left[\mathrm{Cu}=64, \mathrm{Mv}=22.4 \mathrm{dm}^{3}, \mathrm{IF}=96500 \mathrm{C}\right](10 \mathrm{mks}) \)
c. Explain ionization energy and electronegativity ( 5 mks )
QUESTION 4
a Define the following terms
i. pH
ii. POH
iii, Base
iv, Acid v. Basic salt ( 5 mks )
bv Calculate the pH of a solution which has hydrogen ion concentration \( 4.5 \times 10^{-4} \mathrm{~m}(8 \mathrm{mks} \)
of Differentiate hetween order and molecularity ( 7 mks )
QUESTION 5
a. Calculate the central positive element from the following compounds
i. \( \mathrm{Na}_{2} \mathrm{CO}_{3}{ }^{\circ} \) ii. \( \mathrm{Ca}\left(\mathrm{NO}_{3}\right)_{2} \)
iii. \( \mathrm{H}_{2} \mathrm{PO}_{4} \)
iv. \( \mathrm{SO}_{4}{ }^{2} \)
v. \( \mathrm{CaH}_{2} \)
(10 mks)
b. List three applications of electrolysis ( 3 mks )
c. State four differences between oxidizing agent and reducing agent ( 5 mks )
d. State two uses of oxidation number ( 2 mks )