The impurities in the ores are removed by adding ……………. Oxides of non-metals when dissolved in water generally give ……………. Removal of impurities from a metal by chemical method is called ……………. displaces copper from a solution of copper (II) sulphate. The process in which the concentrated ore is heated below its melting point in the absence or limited supply of air is called ……………. Rock salt is an ore of one of the following metals. The metal which is always present in an amalgam is: Which of the following alloys contains a non-metal as one of the constituents? Which of the following pair of metals exist in their native state in nature? Which of the following is an ore of mercury metal? In stainless steel alloy, iron metal is mixed with: The metal which can be extracted from the bauxite ore is: The number of electrons in its ion Y – will be:
The number of electrons in its ion X + will be: The two elements which can react to form ionic bonds (or ionic compound) are: The atomic numbers of four elements A, B, C and D are 6, 8, 10 and 12 respectively. Which of the following can undergo a chemical reaction? Which of the following is a good conductor of electricity? Generally, non-metals are not conductors of electricity. AnswerĪnswer: (d) Y is a non-metal and Z is a metal. The electronic configurations of three elements X, Y and Z are X – 2, 8 Y – 2, 8, 7 and Z – 2, 8, 2. Which of the following properties is not shown by Z?
Reaction between X and Y, forms compound Z. Which among the following alloys contain non-metal as one of its constituents? Identify the element from the following:Īlloys are homogeneous mixtures of a metal with a metal or non-metal. This is very reactive to air and cannot be kept in open. Which one of the following figures correctly describes the process of electrolytic refining?Īn element A is soft and can be cut with a knife. No change occurred in test tubes A and B but the metal got dissolved in test tube C respectively. A small piece of metal was put in each test tube. Which one of the following four metals would be displaced from the solution of its salts by other three metals?Ģ mL each of concentrated HCl, HNO 3 and a mixture of concentrated HCl and concentrated HNO 3 in the ratio of 3 : 1 were taken in test tubes labelled as A, B and C. An alloy of this metal is used in making aircrafts.
Metal M occurs in the Earth’s crust as its oxide M 2O 3. Which of the following metals are refined by electrolytic refining? Metals are refined by using different methods. Which of the following metals exist in their native state in nature? Which one of the following pairs of metals is present in the alloy? The residue reacted with dilute nitric acid to form a blue solution. Which of the following metals are obtained by electrolysis of their chlorides in molten state?Īn alloy reacted with dilute hydrochloric acid to produce a gas which ‘pops’ a lighted splint. Which of the following acids does not give hydrogen gas on reacting with metals (except Mn and Mg)? Generally metals react with acids to give salt and hydrogen gas. (iv) Bubbles of hydrogen gas formed stick to the surface of calcium. (iii) It reacts less violently with water. What happens when calcium is treated with water? Which of the following properties of aluminium are responsible for the same?ĭue to its semiconductor properties the non-metal used in computer, T.V. Aluminium is used for making cooking utensils.