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Name the products formed when iron filings are heated with dilute hydrochloric acid.
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Which of the following correctly represents a balanced chemical equation?
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Why is it important to balance a skeletal chemical equation?
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Graphite is used as a lubricant in machines because ______.
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The allotrope of carbon which is a good conductor of heat and electricity is ______.
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Lead pencil contains ______.
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From which of the following substance pencil lead is formed?
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Assertion: In an open circuit, the current passes from one terminal of the electric cell to another.
Reason: Generally, the metal disc of a cell acts as a positive terminal.
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Solid calcium oxide reacts vigorously with water to form calcium hydroxide accompanied by liberation of heat. This process is called slaking of lime. Calcium hydroxide dissolves in water to form a solution called lime water. Which among the following is (are) true about slaking of lime and the solution formed?
- It is an endothermic reaction
- It is an exothermic reaction
- The pH of the resulting solution will be more than seven
- The pH of the resulting solution will be less than seven
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Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following correctly represents the type of the reaction involved?
- Displacement reaction
- Precipitation reaction
- Combination reaction
- Double displacement reaction
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Electrolysis of water is a decomposition reaction. The mole ratio of hydrogen and oxygen gases liberated during electrolysis of water is
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Which of the following is(are) an endothermic process(es)?
- Dilution of sulphuric acid
- Sublimation of dry ice
- Condensation of water vapours
- Evaporation of water
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In the double displacement reaction between aqueous potassium iodide .and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?
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Which of the following gases can be used for storage of fresh sample of an oil for a long time?
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The following reaction is used for the preparation of oxygen gas in the laboratory
`2"KClO"_3("s") overset("Heat")underset("Catalyst")(->) 2"KCl"("s") + 3"O"_2 ("g")`
Which of the following statement(s) is(are) correct about the reaction ?
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Which one of the following processes involve chemical reactions?
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In which of the following chemical equations, the abbreviations represent the correct states of the reactants and products involved at reaction temperature?
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Which of the following are combination reactions?
- `2"KClO"_3 overset("Heat")(->) 2"KCl" + 3"O"_2`
- `"MgO" + "H"_2"O" -> "Mg"("OH")_2`
- `4"Al" + 3"O"_2 -> 2"Al"_2"O"_3`
- `"Zn" + "FeSO"_4 -> "ZnSO"_4 + "Fe"`
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Write the balanced chemical equations for the following reactions and identify the type of reaction in each case.
- Nitrogen gas is treated with hydrogen gas in the presence of a catalyst at 773 K to form ammonia gas.
- Potassium hydroxide solution is treated with acetic acid to form potassium acetate and water.
- Ethanol is warmed with ethanoic acid to form ethyl acetate in the presence of concentrated H2SO4.
- Ethene is burnt in the presence of oxygen to form carbon dioxide, water and release heat and light.
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Write the balanced chemical equations for the following reactions and identify the type of reaction in each case.
- Iron (III) oxide reacts with aluminum and gives molten iron and aluminum oxide.
- Magnesium ribbon is burnt in an atmosphere of nitrogen gas to form solid magnesium nitride.
- Chlorine gas is passed in an aqueous potassium iodide solution to form potassium chloride solution and solid iodine.
- Ethanol is burnt in air to form carbon dioxide, water and releases heat.
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