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प्रश्न
Define: Chemical combination reaction
उत्तर
When two or more substances combine (a mixture of compounds) to form a single product, then the reaction is called a combination reaction.
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संबंधित प्रश्न
Why is respiration considered an exothermic reaction? Explain.
Find the odd man out:
Camphor, Ammonium Chloride, Naphthalene balls, Sugar
One of the following is an endothermic reaction. This is:
(a) combination of carbon and oxygen to form carbon monoxide
(b) combination of nitrogen and oxygen to form nitrogen monoxide
(c) combination of glucose and oxygen to form carbon dioxide and water
(d) combination of zinc and hydrochloric acid to form zinc chloride and hydrogen
What type of reaction is represented by the following equation?
CaO + H2O → Ca(OH)
What type of reaction is represented by the following equation?
2 Ca + O2 → 2CaO
What type of chemical reaction take place when a magnesium wire is burnt in air?
What type of chemical reaction take place when ammonia and hydrogen chloride are mixed?
What type of chemical reaction is represented by the following equation?
A + B → C
what tpye of reaction is the following:
2K + Cl → 2KCl
Give one example of a combination reaction which is also endothermic.
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
What happens during a chemical reaction ?
What do you understand by a chemical bond ?
Give one example each of which illustrates the following characteristics of a chemical reaction:
change of colour
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 ?
Fill in the blank
A reaction in which two or more substances combine to form a single substance is called a ............ reaction.
Fill in the blank
The chemical reaction between hydrogen and chlorine is a ................ reaction
What are chemical combination or synthesis reactions ? Chemical combination or synthesis:
What effect does an increase in concentration of H+ (aq.) in a solution have on the pH of solution?
Explain the terms with examples.
Combination reaction
Classify the following reaction into different type:
CaO(s) + H2O(l) → Ca(OH)2(aq)
Give a balanced equation for –
A direct combination reaction involving two elements, one of which is a non-metal
Select the correct answer for the statement given below:
The product formed during direct combination reaction of carbon dioxide and water.
Complete the statement by filling in the blank with the correct word:
Direct combination reaction of phosphorus pentoxide with water gives _______.
Which changes occur during chemical changes?
H2(g) + Cl29(g) → 2HCl(g) is a ______
Combustion reactions are always ____________.
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 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?
Give the chemical reaction when a few pieces of slaked lime are added to a beaker half-filled with water. Will it be an endothermic or exothermic reaction?
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.
- Assertion: Rusting of Iron is endothermic in nature.
- Reason: As the reaction is slow, the release of heat is barely evident.
