SS 2 Third Term Examination CHEMISTRY

CLASS: S S 2

SUBJECT: CHEMISTRY

1. What is the electronic configuration of sodium?

1S25²2P⁶35² (b)15²25²2P⁶35² (c)15²25²2P⁶35¹

(d) 15²25²2P⁶35⁰ (e) 15²2P⁶35²3p⁶45¹

2. Which of the following statements is true?

(a)An increase in temperature increases number gas molecules.

(b)Increase in temperature does not affect kinetic energy

©Increase in temperature is proportimal to volume

(d) decrease in pressure decrease number of gasmol.

3. An element is said to be electronegative if

a.If is an halogen

b.If is an Alkali earth metal

c.If is an Alkali

4.What is the consequence of increasing the equilibrium reaction? Zn0(g) +theg = Zn (g) + H₂0(L)

a.Equilibrium is driven to the left

b.Equilibrum is driven to the right

c.There is no effect

d.More Zn0(s) is produces

5. An isotope has an atomic number of 17 and a mass number of 36, which of the following gives the correct number of neutron and protons in an atom of the isotope?

Neutrons Protons

A 53 17

B 17 36

C 19 17

D 36 17

Use this information to answer the following questions

Four elements, P,Q,R,S, have atomic number 4,10,12 AND 14 Respectively.

6.Which is a notable gas a. P B. Q C. R D. S

7.Which is an ALKALI-METAL a. P b. Q C. R d. S

8.Which is an ALKALI- EARTH METAL A. P B. Q C. R D. S

9. The element with electronic configuration 1s²,2S²,2P³ is a. oxygen b. Chlorine c. nitrogen d. calcium

10. How many electron are in L shell a. 2 b. 5 c. 8 d. 16

11. Which of the following reaction is endothermic

a. C_[s] + O_{2 [g]} — CO_2[g]

b. CaO(s) + H₂O© → (a{OH]₂cs)

c.Ccs = H₂0 → C0(g) = H2(g)

d. HCIcag) + Na0Hcag) →NaCIcag0 + H₂0©

12.A catalyst speed up the rate of chemical reaction by

a.Taking part in the reaction

b.lowering the activation energy of the reaction.

c.increase the heat content

d.increase the activation energy

13. The electronic configuration of two atoms X and Y are as follows:

X –IS²25²2P⁶3S²

Y- IS²25²2P⁶3S²3P⁶4S²

Which of the following statement is correct about the position of elements X and Y in the periodic table

a.X belongs to group 1,Y belongs to period 2

b.X belongs to group 1.Y belongs to period 1

c.X belongs to group 2,Y belongs to period 1

d.X belongs to group 3,Y belongs to period 2

14. The electronic configuration 1S² 2S² 2P⁶ 3S² 3P⁶ is that of a. noble gas b. Group 11 element c.group 3 element d. group vi element

15. Which of the following statements is not correct a. diatomic b. good oxidizing agents c. Highly electronegative d. have high electron affinity

16. An element whose atomic number 19 has the electronic configuration

a. IS²25²2P⁶35²3P⁷

b.15²25²2P⁶35²3P²3P⁶3d1

c.1S²25²2P⁶3S³3P⁶

d.IS²25¹2P⁶35²3P⁶45²

17. Chlorine is used in water treatment as a. a germicide b. decolorizing agent c.an antioxidant d. a coagulating agent

18. The valency of chlorine is a. -1 b. -5 c. -3 d. +1

19. Isotopy is observed in which of the following element a. chlorine b. carbon c. oxygen d. fluorine

20. The position of an element on the periodic table is determined by its a. its density b. its atomic radius c. atomic number d. neutron number

21. What is the molar mass of alkyne with the formula CXH14 [H=1 C= 12] a. 86g b.92g c. 98g d. 110g e. 112g

22. Which of the following is not a separation techniques

a.distillation

b.propiation

c. chromatography

d. distillation

23. Which of the following is not an halogen a. silicon b. fluorine c. astatine d. bromine e. iodine

24. An atom X consist of 6 protons, 6 electrons and 7 neutrons, Which of the following representation of atom is correct

(a)¹³₆X

(b)¹³₇x

(c)¹⁹₆ X

(d)¹⁹₇ X

25.The following atoms of carbon ¹²_6C,¹³_{6C and} ¹⁴_6C can be described as a.

allostropes b. isomas c. isotopes d. isotones

26. How many electrons are there in ₄Be²⁺ a. 2 b. 4 c. 5 d. 6

27.An atom of an element X gains two electrons.The symbol of the ion formed is a. X b. X+ c. X^{2+ D} d.X^2-

28.In the periodic table,all the elements within the same group have the same.

A.number of neutron

b. number of valency electron

c. numbers of isotopes

d. atomic number

29.In the periodic table,alkaline earth metals can be found in group

a. 1

b. 11

c. vi

d. vii

30.Which of the following instruments is used in detecting the presence of radiation

a. cathode ray tube

b. Greiger-Muller Counter c.

Mass spectrometer

d. X-ray tube

31.Which of the following elements is a metalloid a. carbon b. oxygen c. silicon d. sodium

32.The shape of graphite crystal is a. tetrahydra b. pyramidal c. hexagonal d. octahedral

33.Which of the following ions has the electronic configuration 2,8,8 a. Na+

b.Mg²⁺ c. F d. Cl^—

34.An element with electronic configuration of 1S,2S,2P would have the combining power of a. 0 b. 2 c. 6 d.8

35.Which of the following has the electronic configuration; 1S 2S 2P 3S 3P[Na,Al,N,S] a.0 b. 2 c. 6 d. 8

36.Find the number of neutons in an atom represented by ⁴⁶₂₁ X

a. 21 b. 24 c. 45 d. 66

37.The activation energy of a reaction can be altered by a. adding reduction agent b. applying a higher pressure c. using a catalyst d. changing the temperature

38.The phenomenon observed when particlesof colloidal solutionblock the part of light rays and scatter them is known as a.diffusion b. tyndal effect c.dialysis d. Brownian movement

39.Which of the following substances causes the depletion of the ozone layer in the atmosphere a. CO₂ b. Chloroform carbon c.Sulphur [iv]oxide d. hydrocarbon

40. A consequence of global warming is a. air pollution b. water pollution c. Increased humidity d. Flooding

30.Which of the following instruments is used in detecting the presence of radiation

a. cathode ray tube

b. Greiger-Muller Counter c.

Mass spectrometer

d. X-ray tube

31.Which of the following elements is a metalloid a. carbon b. oxygen c. silicon d. sodium

32.The shape of graphite crystal is a. tetrahydra b. pyramidal c. hexagonal d. octahedral

33.Which of the following ions has the electronic configuration 2,8,8 a. Na+

b.Mg²⁺ c. F d. Cl^—

34.An element with electronic configuration of 1S,2S,2P would have the combining power of a. 0 b. 2 c. 6 d.8

35.Which of the following has the electronic configuration; 1S 2S 2P 3S 3P[Na,Al,N,S] a.0 b. 2 c. 6 d. 8

36.Find the number of neutons in an atom represented by ⁴⁶₂₁ X

a. 21 b. 24 c. 45 d. 66

37.The activation energy of a reaction can be altered by a. adding reduction agent b. applying a higher pressure c. using a catalyst d. changing the temperature

38.The phenomenon observed when particlesof colloidal solutionblock the part of light rays and scatter them is known as a.diffusion b. tyndal effect c.dialysis d. Brownian movement

39.Which of the following substances causes the depletion of the ozone layer in the atmosphere a. CO₂ b. Chloroform carbon c.Sulphur [iv]oxide d. hydrocarbon

40. A consequence of global warming is a. air pollution b. water pollution c. Increased humidity d. Flooding

SECTION A

ANSWER ALL THE QUESTIONS IN THIS SECTION

1a, What is the allotropes of carbon

b.Name two products of destructive distillation of coal and state one use of it.

c. ^a _p X ^r _p X

1.Give the relationship between the two atoms

2.state the difference between them

3.what phenomenon is illustrated above

2a.State three types of separation techniques?

(b) Write the electronic configuration of ₃₀Zn

©what is the common name given to the group vii elements

3copy and complete this table

(b)The electronic configurations 0f atoms of the elements A,B,C,D are as follows:

(A)1S² 25²2P²

(b)1S²25¹

©IS²25²2P¹

(d)IS²25²

State which of the elements is

(i)Divalent

(ii)Belong to group III the period table

(iii)Is an Alkali earth metal

c. Define isotopy and Allotropy

4. Define the following

(a) Atom (b) Molecule (c)Valency (d)compound

(b) List three differences between chemical and physical change

©Differenciate between an acid and Alkali

(5)Write the characteristics of

(i) Electrovalent elements

(ii)Alkali earth metals

(b)State the lechatelier’s principle

©State and explain three factors that affect rate of reaction

SECTION C

Answer one question in this part

(6)Define mole, what is a molar solution

(b)State and explain three factors that affect equilibrium

©What is Avogadro’s constant

(7)Define relative molecular mass

(b) Write the equilibrium constant for this equation

H_{2(g) +} 0_2(g→ H₂0_(c)

©Define Acid Rain