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प्रश्न
A metal ribbon 'X' bums in oxygen with a dazzling white flame forming a white ash 'Y'. The correct description of X, Y and the type of reaction is:
पर्याय
X = Ca; Y = CaO;
Type of reaction = Decomposition
X = Mg; Y = MgO;
Type of reaction = Combination
X = Al; Y = Al2O3;
Type of reaction = Thermal decomposition
X = Zn; Y = ZnO;
Type of reaction = Endothermic
उत्तर
X = Mg; Y = MgO;
Type of reaction = Combination
Explanation:
In this reaction, magnesium and oxygen combine to create magnesium oxide.
\[\ce{2Mg + O_2 ->2MgO}\]
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संबंधित प्रश्न
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
What type of reaction is represented by the following equation?
2 Ca + O2 → 2CaO
When hydrogen burns in oxygen, water is formed and when water is electrolysed, then hydrogen and oxygen are produced. What type of reaction takes place:
(a) in the first case?
(b) in the second case
Give one example each of which illustrates the following characteristics of a chemical reaction:
change of colour
Define: Chemical combination reaction
Which changes occur during chemical changes?
In which of the following chemical equations, the abbreviations represent the correct states of the reactants and products involved at reaction temperature?
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?
Balance the following chemical equation and identify the type of chemical reaction.
`"Na"("s") + "S"("s") overset("(Fuse)")(->) "Na"_2"S"("s")`
Read the text below and answer the questions that follow:
A small amount of hydrochloric acid was taken in a test tube. The test tube was heated. A glass rod was dipped in the ammonia solution and held on the top of the test tube. A white smoke was seen emanating from the tip of the glass rod.
- What must have happened?
- Which colour of gas is formed?
- Write the chemical equation for the reaction.
