Given below is a diagram showing the placement of five different oxides. With respect to the given diagram answer the following questions:
(a) Name the type of oxide represented in region X in the diagram.
(b) Identify the oxide which has been incorrectly placed in the above diagram.
(c) Name the oxide from the above diagram which will form an alkali when dissolved in water.
(a) Amphoteric oxides
(b) Copper(II) oxide is placed incorrectly. It is a basic oxide, but it is shown under acidic categories.
(c) Sodium oxide (Na2O) is the oxide that will form an alkali when dissolved in water:
\mathrm{Na_2O + H_2O \rightarrow 2NaOH}More ICSE Moderate level questions
P, Q, R and S are the different methods of preparation of salts. P – Simple displacement Q – Neutralisation by titration R – Precipitation S – Direct combination Choose the most appropriate method to prepare the following salts: (a) PbCl2 (b) FeCl3 (c) Na2SO4
Complete the following sentences by choosing the correct word(s) from the brackets: (a) ............... solution forms a coloured precipitate with ammonium hydroxide which is soluble in excess of ammonium hydroxide. [Ferrous chloride / Copper nitrate] (b) Zinc blende is converted to zinc oxide by ................ [Calcination / Roasting] (c) ............... conducts electricity by the movement of ions. [Molten iron / Molten sodium chloride] (d) The reaction that takes place at the anode during the electrolysis of aqueous Sodium argentocyanide with silver electrodes is ................ [Ag ⟶ Ag+ + e-/ Ag+ + e- ⟶ Ag] (e) The salt formed when ZnO reacts with hot concentrated NaOH is ............... . [sodium zincate / zinc hydroxide]
State the terms for the following: (a) Undistilled alcohol containing a large amount of methanol. (b) A salt formed by the partial replacement of the hydroxyl group of a di-acidic or a tri-acidic base by an acid radical. (c) Organic compounds having the same molecular formula but different structural formula. (d) The tendency of an atom to attract the shared pair of electrons towards itself when combined in a compound. (e) The type of covalent bond in which electrons are shared unequally between the combining atoms.
Which pair of reactants can be best used to produce lead (II) sulphate? (a) Sulphuric acid + Lead (b) Sulphuric acid + Lead hydroxide (c) Sodium sulphate + Lead nitrate (d) Potassium sulphate + Lead oxide
Convert the following reactions into a balanced chemical equation: (a) Ammonia to nitric oxide using oxygen and platinum catalyst. (b) Sodium hydroxide to sodium sulphate using sulphuric acid. (c) Ferrous sulphide to hydrogen sulphide using hydrochloric acid.
K, L and M are beakers containing three different solutions as shown below. Name the beaker which: (a) contains only ions. (b) contains only molecules. (c) has pH less than 7.
Complete and balance the following equations: (a) Al2O3 + 2NaOH ⟶ (b) C2H5COONa + NaOH ⟶ (c) C2H4Br2 + alcoholic KOH ⟶
Given below are some chemicals. Lead nitrate, Copper, Hydrochloric acid, Lead oxide, Iron, Sodium carbonate, Copper carbonate, Chlorine Using suitable chemicals from the box given above, write balanced chemical equations for the preparation of the following salts. (Note: The chemicals may be used more than once, if needed.) (a) Lead (II) carbonate (b) Copper (II) chloride (c) Iron (II) chloride
Match the following: Column A Column B (a) ZnCl2 from Zn 1. Precipitation (b) KNO3 from KOH 2. Direct combination (c) CaCO3 from CaCl2 3. Displacement 4. Neutralization
Calcium carbonate reacts with dilute hydrochloric acid as given below: (a) What is the mass of 5 moles of calcium carbonate? (Relative molecular mass of calcium carbonate is 100) (b) How many moles of HCl will react with 5 moles of calcium carbonate? (c) What is the volume of carbon dioxide liberated at S.T.P. at the same time?
Mohan has three solutions P, Q and R having a pH of 13, 5 and 2 respectively. Which of the above solutions P, Q or R: (a) will react with Magnesium to liberate hydrogen gas? (b) will liberate ammonia gas when it reacts with ammonium chloride? (c) will contain molecules as well as ions?
Arrange the following as per the instructions given in the brackets: (a) Carbon, Fluorine, Beryllium (decreasing order of atomic size) (b) Sulphuric acid, Phosphoric acid, Acetic acid (increasing order of number of replaceable H atoms per molecule) (c) Potassium, Lithium, Sodium (increasing order of ionization potential)
