Chemistry Science Paper 2 2015-2016 (English Medium) ICSE Class 10 Question Paper Solution

Choose the word or phrase from the brackets which correctly complete the following statement:

Metals are good ______ (oxidizing agents/reducing agents) because they are electron ______ (acceptors/donors).

Electrovalent compounds have ________________ (high / low) melting points.

Higher the pH value of a solution, the more ______ it is.

Acidic

Alkaline

_____________ (AgCl / PbCl₂), a white precipitate is soluble in excess NH₄OH

Conversion of ethene to ethane is an example of ______.

Hydration

Hydrogenation

An element with the atomic number 19 will most likely combine chemically with the element whose atomic number is ______.

17

11

28

20

Choose the correct answer from the options given below:

The ratio between the number of molecules in 2g of hydrogen and 32g of oxygen is:

[Given that H = 1, O = 16]

1: 2

1: 0.01

1: 1

0.01: 1

Choose the correct answer from the options given below :

The two main metals in Bronze are:

(A) Copper and zinc

(B) Copper and lead

(C) Copper and nickel

(D) Copper and tin

Choose the correct answer from the options given below :

The particles present in strong electrolytes are :

(A) Only molecules

(B) Mainly ions

(C) Ions and molecules

(D) Only atoms

The aim of the Fountain experiment is to prove that ______.

HCl turns blue litmus red.

HCl is denser than air.

HCl is highly soluble in water.

HCl fumes in moist air.

Write balanced chemical equation for action of warm water on AIN.

Write balanced chemical equations for Action of hot and concentrated Nitric acid on copper

Write a balanced chemical equation for the action of hydrochloric acid on sodium bicarbonate.

Write balanced chemical equations for the action of dilute sulphuric acid on sodium sulphite.

Write balanced chemical equations for Preparation of ethanol from Ethyl Chloride

State your observation when dilute hydrochloric acid is added to a lead nitrate solution and the mixture is heated.

State your observations when Barium chloride solution is mixed with Sodium Sulphate Solution.

State your observations when Concentrated Sulphuric acid is added to Sugar Crystals

State your observations when Dilute Hydrochloric acid is added to Copper carbonate

State your observations when Dilute Hydrochloric acid is added to Sodium thiosulphate.

Identify the term/substance in the following:

The tendency of an atom to attract electrons to itself when combined in a compound.

Identify the term/substance in the following:

The method used to separate ore from gangue by preferential wetting

Identify the term/substance in the following:

The catalyst used in the conversion of ethyne to ethane.

Identify the term/substance in the following:

The type of reactions alkenes undergo.

Identify the term/substance in the following:

The electrons present in the outermost shell of an atom.

A gas of mass 32 gms has a volume of 20 liters at S.T.P. Calculate the gram molecular weight of the gas.

How much Is Calcium oxide formed when 82g of calcium nitrate is heated? Also, find the volume of nitrogen dioxide evolved :

2Ca(NO₃)₂ → 2CaO+4NO₂+O₂

_{(Ca = 40 , N = 14,O = 16)}

Match the salts given in Column I with their method of preparation given in Column II.

Write the IUPAC names of the following:

Write the IUPAC names of the following:

Write the IUPAC names of the following:

Rewrite the following sentences by using the correct symbol > (greater than) or < (less than) in the blanks given

The ionization potential of potassium is _________________ that of sodium.

Rewrite the following sentences by using the correct symbol > (greater than) or < (less than) in the blanks given

The electronegativity of iodine is ___________ that of Chlorine

Use the letters only written in the Periodic Table given below to answer the questions that Follow :

1) State the number of valence electrons in atom J.

2) Which element shown forms ions with a single negative charge?

3)Which metallic element is more reactive than R?

4) Which element has its electrons arranged in four shells?

If an element has a low ionization energy then it is likely to be ______________ (metallic / non metallic).

If an element has seven electrons in its outermost shell then it is likely to have the ______________ atomic size among all the elements in the same period.

Largest 

Smallest

The following table shows the electronic configuration of the elements W, X, Y, Z:

Answer the following questions based on the table above:

1) What type of Bond is formed between :

a) W and X

b) Y and Z

2) What is the formula of the compound formed between :

a) X and Z

b) W and X

Write a balanced chemical equation for Burning of ethane in the plentiful supply of air.

Write a balanced chemical equations for Action of water on Calcium carbide

Write a balanced chemical equations for Heating of Ethanol at 170°C in the presence of conc. Sulphuric acid

Give the structural formulae of 2-methylpropane.

Give the structural formulae of Ethanoic acid.

Give the structural formulae of Butan – 2 -ol

The equation for the reaction when compound A is bubbled through bromine dissolved in carbon tetrachloride is as follows:

1) Draw the structure of A.

2) State your observation during this reaction.

Fill in the blanks using the appropriate words given below :

(Sulphur dioxide, nitrogen dioxide, Nitric oxide, Sulphuric acid)

Cold, dilute nitric acid reacts with copper to give ___________.

Fill in the blanks using the appropriate words given below :

(Sulphur dioxide, nitrogen dioxide, Nitric oxide, Sulphuric acid)

Hot, concentrated nitric acid reacts with sulphur to form ______________.

Identify the gas evolved and give the chemical test in the following cases

Dilute hydrochloric acid reacts with sodium sulphite.

Identify the gas evolved and give the chemical test in the following cases

Dilute hydrochloric acid reacts with iron (II) sulphide.

State your observations when ammonium hydroxide solution is added drop by drop and then in excess to each of the following solutions :
1) Copper sulphate solution

2) Zinc sulfate solution.

Write equations for the reactions taking place at the two electrodes (mentioning clearly the name of the electrode) during the electrolysis of Acidified copper sulphate solution with copper electrodes

Write equations for the reactions taking place at the two electrodes (mentioning clearly the name of the electrode) during the electrolysis of Molten lead bromide with inert electrodes

Name the product formed at the anode during the electrolysis of acidified water using platinum electrodes.

Name the metallic ions that should be present in the electrolyte when an article made of copper is to be electroplated with silver.

A gas cylinder contains 12 x 10²⁴ molecules of oxygen gas.

If Avogadro’s number is 6 x 10²³; Calculate:

1)The mass of oxygen present in the cylinder.

2) The volume of oxygen at S.T.P. present in the cylinder. [O = 16]

A gaseous hydrocarbon contains 82.76% of carbon. Given that its vapor density is 29, find its molecular formula. [C = 12, H = 11]

The equation 4NH₃ + 5O₂ → 4NO + 6 H₂O, represents the catalytic oxidation of ammonia. If 100 cm³ of ammonia is used calculate the volume of oxygen required to oxidize the ammonia completely

By drawing an electron dot diagram show the formation of Ammonium ion [Atomic No.: N = 7 and H = 1]

Name the gas evolved when the following mixtures are heated:

Calcium hydroxide and Ammonium Chloride

Name the gas evolved when the following mixtures are heated.

Sodium Nitrite and Ammonium Chloride

Write balanced chemical equations for the following:

When the excess of ammonia is treated with chlorine.

Write balanced chemical equations for the following:

An equation to illustrate the reducing nature of ammonia.

A, B, C, and D summarize the properties of sulphuric acid depending on whether it is dilute or concentrated.

A = Typical acid property

B = Non volatile acid

C = Oxidizing agent

D = Dehydrating agent

Choose the property (A, B, C or D) depending on which is relevant to each of the following

1) Preparation of Hydrogen chloride gas

2) Preparation of Copper sulphate from copper oxide.

3) An action of conc. Sulphuric acid on Sulphur.

Give reasons why Sodium Chloride will conduct electricity only in the fused or aqueous solution state.

Give reasons why In the electroplating of an article with silver, the electrolyte sodium argentocyanide solution is preferred over silver nitrate solution.

Give reasons why Although copper is a good conductor of electricity, it is a non-electrolyte.

Name the solution used to react with Bauxite as a first step in obtaining pure aluminum oxide, in the Baeyer’s process

Write the equation for the reaction where the aluminum oxide for the electrolytic extraction of aluminum is obtained by heating aluminum hydroxide.

Name the compound added to pure alumina to lower the fusion temperature during the electrolytic reduction of alumina.

Write the equation for the reaction that occurs at the cathode during the extraction of aluminum by electrolysis.

Explain why it is preferable to use a number of graphite electrodes as the anode instead of a single electrode, during the above electrolysis.

State what would you observe when Washing Soda Crystals are exposed to the atmosphere

State what would you observe when The salt ferric chloride is exposed to the atmosphere

Identify the cations in the following case:

NaOH solution, when added to the Solution (A), gives a reddish brown precipitate

Identify the cations in the following case :

NH₄OH Solution, when added to the Solution (B), gives white ppt which does not dissolve in excess.

Identify the cations in the following case:

NaOH Solution, when added to Solution (C), gives white ppt which is insoluble in excess