Day 130: CBSE Class 10 Science
5 questions. Try each one first, then open its answer.
Question 1
Metals and Non-metals. Asked once: 2026 (same type asked 3 times)
29 (A)(i) Give reasons for the following : (I) Ionic compound have generally high melting points and boiling points. (II) Solder, an alloy of lead and tin, is used for welding electrical wires. (III) Carbon cannot reduce the oxides of Na or Mg. (ii) The reaction of compound ‘X’ with aluminium is used to join railway tracks : (I) Identify the compound ‘X’. (II) Name the reaction. (III) Write the balanced chemical equation of the reaction of compound ‘X’ with aluminium.Question 2
Metals and Non-metals. Asked once: 2024 (same type asked 3 times)
Two statements are given, one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer from the options given below.20Assertion (A) : Metals in the middle of activity series are found in nature as sulphides or carbonates. Reason (R) : The sulphide ores are calcinated whereas carbonate ores are roasted to extract metals from them.Tap an option to check your answer.
Question 3
Our Environment. Asked once: 2023 (same type asked 3 times)
33 (b)(i) Construct a food chain of four trophic levels comprising the following : Hawk, snake, plants, rat. (ii) 20,000 J of energy was transferred by the producers to the organism of second trophic level. Calculate the amount of energy that will be transferred by organisms of the third trophic level to the organisms of the fourth trophic level.Question 4
Our Environment. Asked once: 2024 (same type asked 3 times)
15A food chain will be more advantageous in terms of energy if it hasTap an option to check your answer.
Question 5
Our Environment. Asked once: 2026 (same type asked 3 times)
6In terms of various trophic levels of a food chain, which of the following organisms belong to the same level ?Tap an option to check your answer.