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प्रश्न
Give one example of an endothermic reaction.
उत्तर
Example of endothermic reaction: Barium hydroxide on reacting with ammonium chloride produces ammonia, water and barium chloride. It also results in decrease in temperature, as it consumes heat energy.
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संबंधित प्रश्न
Balance the following equation:
Pb3O4 → PbO + O2
\[\ce{MnO2 + 4HCl -> MnCl2 + 2H2O + Cl2}\]
0.02 moles of pure MnO2 is heated strongly with conc. HCl. Calculate the mass of acid required.
A chemical reaction is generally accompanied by certain external indications or characteristics. These include – change of – (a) colour (b) state (c) smell (d) evolution of gas (e) formation of precipitate (f) evolution or absorption of heat. With reference to change of colour – state the change in colour seen when the following are heated – mercury [II] oxide.
What is meant by ‘reactants’ and ‘products’ in a chemical equation?
Balance the following simple equation:
Al + H2O → Al2O3 + H2
Match the columns.
| Reactants | Products | Types of chemical reaction | ||
| 1. | MgH2 | → | Mg + H2 | Endothermic |
| 2. | 2H2S + SO2 | → | 3S + 2H2O | Oxidation |
| 3. | CaO + H2O | → | Ca(OH)2 + heat | Exothermic |
| Redox | ||||
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Balance the given chemical reaction as per the instructions below.
\[\ce{NaOH + H2SO4 -> Na2SO4 + H2O}\]
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Reema took 5ml of Lead Nitrate solution in a beaker and added approximately 4ml of Potassium Iodide solution to it. What would she observe?
Three beakers labelled as A, B and C each containing 25 mL of water were taken. A small amount of NaOH, anhydrous CuSO4 and NaCl were added to the beakers A, B and C respectively. It was observed that there was an increase in the temperature of the solutions contained in beakers A and B, whereas in case of beaker C, the temperature of the solution falls. Which one of the following statement(s) is(are) correct?
- In beakers A and B, exothermic process has occurred.
- In beakers A and B, endothermic process has occurred.
- In beaker C exothermic process has occurred.
- In beaker C endothermic process has occurred.
