9th Class Chemistry Guess Paper 2021

9th Class Chemistry Guess

 

Questions # 1

  • Give two properties of neutrons.
  • How many neutrons are present in C-12 and C-13?
  • Do you know any element having no neutrons in its atoms?

Questions # 2

  • Why the second ionization energy of an element is higher than first one?
  • What do you mean by blocks in a periodic table and why elements were placed in blocks?
  • For an element Z = 92, A = 238. Calculate the number of electron and proton in it.
  • What is the definition of the element according to the Robert Boyle?
  • What is the significance of the symbol of an element?
  • Define Boyle’s Law and verify with an example.
  • What type of elements from metallic bond?
  • Define Avogadro’s number.
  • Which element has the highest electro negativity?
  • What type of elements have tendency of sharing of electrons?
  • Why and how elements arranged in a period?
  • What type of elements are metals?
  • Write down the names of elements of group 1 with their symbols?
  • Define Boyle’s rule?

Questions # 3

  • Write two chemical properties of metals and non-metals.
  • Define metal, give two examples.
  • Write down the name of four least reactive metals.
  • Compare any four physical properties of metals and non-metals.
  • What are important physical characteristics of metals?
  • Why reactivity of metals increase drown the group?
  • How non-metals are essential part of our body structure?
  • Which metal is used for metal work?
  • State the physical properties of metals
  • What is the trend of variation it densities of alkali metals?
  • Metals are good conductor of electricity. Why?
  • What are transition metals?
  • How oxygen reacts with group II A metals?

Questions # 4

  • Why silver and gold are least reactive?
  • Give properties and uses of gold?
  • Which is lighter than aluminum of gold?
  • Give the applications of silver. Why platinum is used for making Jewellery?
  • Can pure gold be used for making electrical wires?

Questions # 5

  • Give the Properties of dipole-dipole forces.
  • Define dipole interactions. How are they created?

Questions # 6

  • Write down any two properties of canal rays.
  • Give two properties of positive rays.
  • Write down two properties, of cathode rays.
  • What conclusion you derive from these properties.
  • How are cathode rays produced?
  • What is the nature of charge on cathode rays?
  • What are its five major characteristics?

Questions # 7

  • Define atomic mass unit. Why is it needed?
  • Define atomic number and mass number.
  • What are SI units of atomic radius?
  • Define Tri-atomic and Hetero-atomic.
  • Why do atoms react?
  • How can you define atomic radius?
  • What is Luther Meyer’s atomic volume curve?
  • What is meant by atomic size? Write its unit.
  • What are the salient features of Rutherford’s atomic model?
  • How Rutherford discovered that atom has a nucleus located at the centre of the atom?
  • What are the defects of Rutherford atomic model?
  • Give two postulates of Bohr’s atomic theory.
  • How it is related to gram?
  • What is the relative atomic mass?
  • Find out the mass of 3 moles of oxygen atoms.
  • Why the size of atom decreases in a period?
  • How to atoms follow octet rule?
  • What is trend of atomic radius in period and group?
  • Calculate the number of atoms in 10 grams of Aluminum (Al).
  • Differentiate between Homo atomic and Hetero atomic molecules.
  • How is periodicity of properties dependent upon number of protons in an atom?
  • Calculate the number of moles, number of molecule atoms present in 6 grams of water.
  • How was it proved that electrons are fundamental particles of an atom?
  • Give basic postulates of Bohr’s atomic theory.
  • Give the electronic configuration of carbon atom.

Questions # 8

  • Give the physical properties of sodium and its uses.
  • Write any two uses of sodium.
  • Why does sodium make ionic bond with chlorine?
  • Why does sodium forma chemical bound with chloride?
  • Why magnesium is harder than sodium.

Questions # 9

  • Write down two uses of calcium.
  • Give physical properties of calcium and its uses.
  • Why calcium is more electropositive tan to magnesium?
  • Write the chemical formulae of Aluminium Sulphate and Calcium Phosphate.

Questions # 10

  • Define and explain Charles’s Law of gasses.
  • Whether the density of gases increases on cooling? Explain.
  • Why are the densities of gases lower than that of liquids?
  • Why the gases are compressible?
  • Why noble gases are not reactive?
  • Can you cool a gas by increasing it volume?

Questions # 11

  • What is meant by volume / volume %?
  • What do you mean by %-mass / mass?
  • Give the example and formula of mass by volume percent.
  • There are 3.01 x 1023 molecules of CO2 present in a container.
  • Calculate the number of moles of coal in the given mass.
  • Calculate the number of moles and its mass. You have a piece of coal (carbon) weighing 9.0 grams.
  • How can you differentiate between molecular formula, formula mass and empirical formula?
  • Calculate the number of moles of coal in the given mass.

 

You can use the rich libraries that provide access to hundreds of international scientific journals and databases. In many cases, training also includes internships. This can be a separate plus for your resume, especially when it comes to a large bank or an international company. Very often, such a component of training becomes a prologue to starting work within the walls of large international companies.

It is important to note that student employment departments operating at universities are also Western inventions. These departments have a staff of consultants who have reliable information about the requests of employers that can facilitate assistance in organizing the first contact with them (in the form of job fairs and interviews here at the university). This extremely effective tool helps graduates to take the first step on the career ladder.

One of the success components of the best foreign universities is their dynamism and focus on innovation. For example, foreign universities are increasingly using the most advanced multimedia tools in the educational process. All the achievements of technological progress are put at the service of students, helping them to acquire the necessary knowledge and skills, become real professionals in their field.

Spread Knowledge
Newsletter

Get More Stuff Like This IN YOUR INBOX

Subscribe to our Mailing List and get interesting Stuff and updates to your Inbox


Click Here to Leave a Comment Below 0 comments

Leave a Reply: