Sample Paper 10

SUMMATIVE ASSESSMENT –I SCIENCE Class – X Time allowed: 3 hours Maximum Marks: 90 General Instructions: (i) All questions are compulsory. (ii) The question paper comprises of two sections, A and B. You are to attempt both the sections. (iii) Questions 1 to 4 in section A are one mark questions. These are to be answered in one word or in one sentence. (iv) Questions 5 to 11 in section A are two marks questions. These are to be answered in about 30 words each. Questions 12 to 23 in section A are three marks questions. These are to be answered in about (v) 50 words each. (vi) Questions 24 to 27 in section A are five marks questions. These are to be answered in about 70 words each. (vii) Questions 28 to 43 in section B are multiple choice questions based on practical skills. Each question is a one mark question. You are to select one most appropriate response out of the four provided to you. SECTION-A 1. 2. 3. 4. Write a balanced chemical equation for a chemical combination reaction. Name the metal which has very low melting point and can melt with heat of your palm. Why is the box of a solar cooker covered with a glass plate ? The voltage - current (V-I) graph of a metallic conductor at two different temperature T1 and T2 is shown below. At which temperature is the resistance higher ?

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Why is sodium stored in kerosene ? (a) Why does blue vitriol change to white on heating ? (b) Write its formula. What happens in a displacement reaction. Justify your answer giving one example. (a) Balance the chemical equation : Fe(s) + H2O(g) Fe3O4(s)+ H2(g) (b) Identify the type of reaction in the equation given below : Na2SO4(aq) + BaCl2(aq) BaSO4(s) + NaCl(aq) State the function of the guard cells. What will happen to the guard cells and stomatal pore when water flows to guard cells ? Name the major constituent of biogas. List three characteristics to prove it as an excellent fuel. How much current will an electric bulb draw from a 220V source, if the