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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
उत्तर
colourless
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संबंधित प्रश्न
Write the balanced chemical equation for the following and identify the type of reaction.
\[\ce{Hydrogen(g) + Chlorine(g) -> Hydrogen chloride (g)}\]
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
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.
Gas A, which is the major cause of global warming, combines with hydrogen oxide B in nature in the presence of an environmental factor C and a green material D to form a six carbon organic compounds E and a gas F. The gas F is necessary for breathing.
(a) What is gas A?
(b) What is the common name of B?
(c) What do you think could be C?
(d) What is material D? Where is it found?
(e) Name the organic compound E.
(f) What is gas F? Name the natural process during which it is released.
what tpye of reaction is the following:
2K + Cl → 2KCl
What type of reaction is represented by the following equation?
CaO + CO2 → CaCO3
Define a combination reaction.
Give one example of a combination reaction which is also exothermic.
Give one example of a combination reaction which is also endothermic.
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
Define a chemical reaction.
What happens during a chemical reaction ?
What do you observe when solid lead nitrate is heated?
Fill in the blank
A reaction in which two or more substances combine to form a single substance is called a ............ reaction.
Explain the following type of chemical reaction, giving two examples for it:
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Explain the terms with examples.
Combination reaction
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\[\ce{CaO{(s)} + H2O(l) -> Ca(OH)2(aq)}\]
This reaction can be classified as:
(A) Combination reaction
(B) Exothermic reaction
(C) Endothermic reaction
(D) Oxidation reaction
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.
Explain the following reaction with their balanced chemical equation.
Ammonia gas reacts with hydrogen chloride.
Which changes occur during chemical changes?
H2(g) + Cl29(g) → 2HCl(g) is a ______
Which of the following are exothermic processes?
(i) Reaction of water with quick lime
(ii) Dilution of an acid
(iii) Evaporation of water
(iv) Sublimation of camphor (crystals)
Which of the following is not a physical change?
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Identify the correct option from the given table which represents the type of reactions occurring in step 1 and step 2.
Balance the following chemical equation and identify the type of chemical reaction.
`"Mg"("s") + "Cl"_2("g") -> "MgCl"_2("s")`
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.
