Give one significant observation when: (a) Barium chloride solution is added to zinc sulphate solution. (b) Lead nitrate is heated strongly. (c) Chlorine gas is passed through moist starch iodide paper.

Give one relevant observation for the following: (a) Sodium hydroxide is added dropwise to Calcium nitrate solution. (b) Dilute Hydrochloric acid is added to Iron (II) sulphide. (c) An amphoteric metal is added to hot concentrated alkali.

Choose the substances given in the box below to answer the following questions: Iron Magnesium sulphite Zinc Sodium sulphide Lead Ferric chloride Copper Ferrous sulphate (a) The metal that will not produce hydrogen gas when reacted with dilute acids. (b) The compound that will produce sulphur dioxide gas when reacted with dilute HCl. (c) The solution of this compound produces dirty green precipitate with NaOH.

Rita added dilute hydrochloric acid to four metals. She recorded her observations in the table given below. While noting her observations she made some errors. Metals Observations 1 copper a gas was given off 2 iron a gas was given off 3 magnesium no gas was given off 4 zinc a gas was given off Which observation(s) made by Rita is/are correct? (a) 1 only (b) 3 only (c) Both 1 and 4 (d) Both 2 and 4

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.

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

Draw the dot and cross structure of the following: (a) An ionic compound formed when Mg reacts with the dilute HCl. (b) A covalent compound formed when H2 reacts with Cl2. (c) The positive ion produced when ammonia gas is dissolved in water. [ Atomic number: Mg = 12, Cl = 17, H = 1, N = 7 ]

Rohit took two different salt solutions in test tubes C and D as shown in the figure below. He added dilute HCl to each of the two test tubes. The products formed in the test tubes C and D are silver chloride and lead chloride respectively. State: (a) one common observation made by Rohit in both the reactions. (b) the observations made by him on addition of excess of ammonium hydroxide to the products formed in: 1. test tube C 2. test tube D

Give balanced equations for the following: (a) Action of dilute hydrochloric acid on ammonium carbonate. (b) Oxidation of sulphur with hot concentrated nitric acid. (c) Reaction of concentrated sulphuric acid with carbon.

Study the table given below. Use only the letters given in the table to answer the questions. Do not identify the elements. IA IIA IIIA IVA VA VIA VIIA 0 E J Q L G M D P N (a) State the valency of element ‘G’. (b) Which element can exhibit catenation? (c) Write the formula of the compound formed between ‘M’ and ‘P’.

Acidulated water is electrolysed using platinum electrodes. Answer the following questions: (a) Why is dilute sulphuric acid added to water? (b) Write the reaction taking place at the cathode. (c) What is the observation at the anode?

Name the gas produced during each of the following reactions: (a) When copper is treated with hot, concentrated nitric acid. (b) When ammonia is burnt in an atmosphere of oxygen. (c) When ferrous sulphide reacts with dilute hydrochloric acid.