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प्रश्न
Explain the terms with examples.
Combination reaction
उत्तर
Combination reaction:
Those reactions in which two or more substances combine to form single substance is called combination reaction
For example : Magnesium and oxygen combine, when heated, to form magnesium oxide.
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संबंधित प्रश्न
A solution of a substance ‘X’ is used for white washing.
- Name the substance ‘X’ and write its formula.
- Write the reaction of the substance ‘X’ named in (i) above with water.
Why is respiration considered an exothermic reaction? Explain.
When crystals of copper sulphate are strongly heated, the residue obtained is ___________.
(A) red in colour
(B) blue in colour
(C) green in colour
(D) colourless
Find the odd man out:
Camphor, Ammonium Chloride, Naphthalene balls, Sugar
What happens chemically when quicklime is added to water filled in a bucket?
A silvery-white metal X taken in the form of ribbon, when ignited, burns in air with a dazzling white flame to form a white powder Y. When water is added to powder Y, it dissolves partially to form another substance Z.
(a) What could metal X be?
(b) What is powder Y?
(c) With which substance metal X combines to form powder Y?
(d) What is substance Z? Name one domestic use of substance Z.
(e) Write a balanced chemical equation of the reaction which takes place when metal X burns in air to form powder Y.
What type of reaction is represented by the following equation?
2 Ca + O2 → 2CaO
what tpye of reaction is the following:
2K + Cl → 2KCl
What type of reaction is represented by the following equation?
CaO + CO2 → CaCO3
Give one example of a combination reaction which is also exothermic.
Consider the following equation of the chemical reaction of a metal M:
4M + 3O2 → 2M2O3
This equation represents:
(a) combination reaction as well as reduction reaction
(b) decomposition reaction as well as oxidation reaction
(c) oxidation reaction as well as displacement reaction
(d) combination reaction as well as oxidation reaction
What happens during a chemical reaction ?
What do you understand by a chemical bond ?
What do you observe when solid lead nitrate is heated?
What do you observe when when dilute sulphuric acid is added to barium chloride solution ?
Classify the following reaction as combination, decomposition, displacement, precipitation and neutralization. Also balance the equation.
\[\ce{CaCO3_{(s)} ->[heat]CaO_{(s)} + CO2_{(g)}}\]
What are chemical combination or synthesis reactions ? Chemical combination or synthesis:
Classify the following reaction into different type:
CaO(s) + H2O(l) → Ca(OH)2(aq)
Give a balanced equation for the following type of reaction:
A reaction of direct combination i.e. synthesis in which twp gases combine to give another gas – which turns lime water milky.
The number of products formed in a synthesis reaction is ______
Define a combination reaction. Give one example of an exothermic combination reaction.
Combustion reactions are always ____________.
In which of the following chemical equations, the abbreviations represent the correct states of the reactants and products involved at reaction temperature?
The respiration process during which glucose undergoes slow combustion by combining with oxygen in the cells of our body to produce energy is a kind of:
The chemical reaction between copper and oxygen can be categorized as ______.
The Salt Story
From: The New Indian Express 9 March 2021
The salt pans in Marakkanam, a port town about 120 km from Chennai are the third largest producer of salt in Tamil Nadu. Separation of salt from water is a laborious process and the salt obtained is used as raw materials for manufacture of various sodium compounds.
One such compound is Sodium hydrogen carbonate, used in baking, as an antacid and in soda acid fire extinguishers.
The table shows the mass of various compounds obtained when 1litre of sea water is evaporated.
| COMPOUND | FORMULA | MASS OF SOLID PRESENT /g |
| Sodium Chloride | NaCl | 28.0 |
| Magnesium Chloride | MgCl2 | 8.0 |
| Magnesium Sulphate | MgSO4 | 6.0 |
| Calcium Sulphate | CaSO4 | 2.0 |
| Calcium Carbonate | CaCO3 | 1.0 |
| TOTAL AMOUNT OF SALT OBTAINED | 45.0 | |
Which compound in the table reacts with acids to release carbon dioxide?
Identify the types of chemical reactions occurring during the combustion of fuel:
Balance the following chemical equation and identify the type of chemical reaction.
`"Mg"("s") + "Cl"_2("g") -> "MgCl"_2("s")`
Balance the following chemical equation and identify the type of chemical reaction.
`"Na"("s") + "S"("s") overset("(Fuse)")(->) "Na"_2"S"("s")`
Balance the following chemical equation and identify the type of chemical reaction.
`"CaO"("s") + "SiO"_2("s") -> "CaSio"_3("s")`
A clear solution of slaked lime is made by dissolving Ca(OH)2 in an excess of water. This solution is left exposed to air. The solution slowly goes milky as a faint white precipitate forms. Explain why a faint white precipitate forms, support your response with the help of a chemical equation.
