THE EDUTAINIANS GUESS SERIES 2023
9th Chemistry
------------------------------------------------------------------------------------
TOP 116 SLO BASED SHORT QUESTIONS
-------------------------------------------------------------------------------------
Chapter # 1
1. Define industrial chemistry and analytical chemistry.
2. How can you differentiate between organic and inorganic chemistry?
3. Give the scope of biochemistry.
4. How does a homogeneous mixture differ from a heterogeneous mixture?
5. What is the relative atomic mass? How is it related to gram?
6. Define the empirical formula with an example.
7. State three reasons why do you think air is a mixture and water is a compound?
8. Explain why are hydrogen and oxygen considered elements whereas water is a
compound.
9. What is the significance of the symbol of an element?
10. State the reasons: the soft drink is a mixture and water is a compound.
11. Classify the following into element, compound, or mixture:
i. He and H ii. CO and Co iii. Water and milk 2
iv. Gold and brass v. Iron and steel
12. Define atomic mass unit. Why is it needed?
13. State the nature and name of the substance formed by combining the
following:
i. Zinc + Copper ii. Water + Sugar
iii. Aluminum + Sulphur iv. Iron + Chromium + Nickel
14. Differentiate between molecular mass and formula mass, which of the
following have a molecular formula?
H O, NaCl, KI, H SO 2 2 4
15. Which one has more atoms: 10 g of Al or 10 g of Fe?
16. Which one has more molecules: 9 g of water or 9 g of sugar (C H O )? 12 22 11
17. Which one has more formula units: 1 g of NaCl or 1 g of KC1?
18. Differentiate between homoatomic and heteroatomic molecules with examples.
19. In which one of the following is the number of hydrogen atoms is more? 2 moles
of HC1 or 1 mole of NH (Hint: 1 mole of a substance contains as much number 3
of moles of atoms as are in 1 molecule of a substance.
Chapter # 2
1. What is the nature of a charge on cathode rays?
2. Give five characteristics of cathode rays.
3. The atomic symbol of a phosphorus ion is given as ^P3~
(a) How many protons, electrons, and neutrons are there in the ion?
(b) What is the name of the ion?
(c) Draw the electronic configuration of the ion.
(d) Name the noble gas which has the same electronic configuration as the
phosphorus ion.
4. Differentiate between shell and subshell with examples of each.
5. An element has an atomic number of 17. How many electrons are present in the K, L, and
M shells of the atom?
6. 3+ Write down the electronic configuration of Al. How many electrons are present in
its outermost shell?
7. Magnesium has electronic configuration 2, 8, 2,
(a) How many electrons are in the outermost shell?
(b) In which subshell of the outermost shell electrons are present?
(c) Why magnesium tends to lose electrons?
8. What will be the nature of a charge on an atom when it loses an electron or when it
gains an electron?
9. For what purpose U-235 is used?
10. A patient has a goiter. How will it be detected?
11. Give three properties of positive rays.
12. What are the defects of Rutherford's atomic model?
13. As long as an electron remains in an orbit, it does not emit or absorb energy. When does
it emit or absorb energy?
Chapter # 3
1. Why are noble gases not reactive?
2. Why Cesium (at. no.55) requires little energy to release its one electron present in the
outermost shell?
3. How is the periodicity of properties dependent upon the number of protons in an atom?
4. Why shielding effect of electrons makes cation formation easy?
5. What is the difference between Mendeleev's periodic law and modern periodic law?
6. What do you mean by groups and periods in the Periodic Table?
7. th Why and how are elements arranged in 4 periods?
8. Why the size of the atom does not decrease regularly in a period?
9. Give the trend of ionization energy in a period.
Chapter # 4
1. Why do atoms react?
2. Why is the bond between an electropositive and an electronegative atom ionic in
nature?
3. Ionic compounds are solids. Justify.
4. More electronegative elements can form bonds between themselves. Justify.
5. Metals are good conductors of electricity. Why?
6. Ionic compounds conduct electricity in solution or molten form. Why?
7. What type of covalent bond is formed in nitrogen molecules.
8. Differentiate between lone pair and bond pair of electrons.
9. Describe at least two necessary conditions for the formation of a covalent
bond.
10. Why HC1 has dipole-dipole forces of attraction?
11. What is a triple covalent bond, explain with an example?
12. What is the difference between polar and non-polar covalent bonds, explain
with one example of each?
13. Why a covalent bond becomes polar?
14. What is the relationship between electronegativity and polarity?
15. Why does ice float on water?
16. Give the characteristic properties of ionic compounds.
17. What characteristic properties do the covalent compound have?
Chapter # 5
1. What is diffusion, explain with an example?
2. Define standard atmospheric pressure. What are its units? How it is related to Pascal?
3. Why are the densities of gases lower than that of liquids?
4. What do you mean by evaporation how it is affected by surface area.
5. Define the term allotropy with examples.
6. In which form sulfur exists at 100 °C.
7. What is the relationship between evaporation and the boiling point of a liquid?
Chapter # 6
1. Why suspensions and solutions do not show the Tyndall effect, while colloids do?
2. What is the reason for the difference between solutions, colloids, and suspensions?
3. Why the suspension does not form a homogeneous mixture?
4. How will you test whether the given solution is a colloidal solution or not?
5. Classify the following into true solution and colloidal solution:
Blood, starch solution, glucose solution, toothpaste, copper sulfate solution, and silver
nitrate solution.
6. Why do we stir paints thoroughly before using them?
7. Which of the following will scatter light and why? sugar solution, soap solution, and
milk of magnesia.
8. What do you mean, like dissolves like? Explain with examples
9. How does the nature of attractive forces of solute-solute and solvent-solvent affect the
solubility?
10. How you can explain the solute-solvent interaction to prepare a NaCl solution?
11. Justify with an example that the solubility of salt increases with the increase in
temperature.
12. What do you mean by volume/volume %?
Chapter # 7
1. Define oxidation in terms of electrons. Give an example.
2. Define reduction in terms of loss or gain of oxygen or hydrogen. Give an
example.
3. What is the difference between valency and oxidation state?
4. Differentiate between oxidizing and reducing agents
5. Differentiate between strong and weak electrolytes.
6. How electroplating of tin on steel is carried out?
7. Why steel is plated with nickel before the electroplating of chromium.
8. How can you explain, that the following reaction is oxidation in terms of the increase
of oxidation number? Al-------> Al + 3e.
9. How can you prove with an example that the conversion of an ion to an atom is an
oxidation process?
10. Why does the anode carry a negative charge in the galvanic cell but a positive charge
in an electrolytic cell? Justify with comments.
11. Where do the electrons flow from the Zn electrode in Daniel's cell?
12. Why do electrodes get their names 'anode' and cathode in a galvanic cell?
13. What happens at the cathode in a galvanic cell?
14. Which solution is used as an electrolyte in Nelson's cell?
15. Name the by-products produced in Nelson's cell?
16. Why is galvanizing done?
17. Why an iron grill is painted frequently?
18. Why is O2 necessary for rusting?
19. In the electroplating of chromium, which salt is used as an electrolyte?
20. Write the redox reaction taking place during the electroplating of chromium?
21. +
In the electroplating of silver, from where do Ag ions come, and where they deposit?
22. What is the nature of the electrode used in the electroplating of chromium?
Chapter # 8
1. Why reactivity of metals increases down the group?
2. State the physical properties of metals.
3. Why nitrogen forms compounds with alkaline earth metals directly?
4. Why the second ionization energy of magnesium is higher than the first one?
5. How oxygen reacts with group II A metals?
6. What is the relationship between electropositivity and ionization energy?
7. Why electropositivity decreases from left to right in a period?
8. How electropositivity depends upon the size and nuclear charge of an atom?
9. Why ionization energies of alkaline earth metals are higher than alkali metals?
10. Why silver and gold are least reactive?
11. Can pure gold be used for making ornaments? If not why?
12. Why copper is used for making electrical wires?
13. What is the trend of variation in densities of alkali metals?
14. Which metal is used for metalwork?
15. Why magnesium is harder than sodium?
16. Why calcium is more electropositive than magnesium?
17. Why ionization energy of Na is less than Mg?
18. Why the ionization energy of Na is more than K?
========================================
Best Of Luck
========================================
Follow us on our social edia platforms:
The Edutainians Educational Project Of Pakistan (Official Account)
The Edutainians Academy (Fb Official Account)
The Edutainians Academy ( Instagram Official Account) ( Intagram Official Account)
==============================================
Admissions Open
Playgroup to FSc
Morning / Evening Coaching Classes
The Edutainians Educational Project of Pakistan
Contact us
0323-4175342
0334-9802115
Nouman Safdar
( Founder The Edutainians )
.png)
