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प्रश्न
Find the odd man out:
Camphor, Ammonium Chloride, Naphthalene balls, Sugar
उत्तर
Sugar
Camphor, ammonium chloride, naphthalene balls are volatile, while sugar is a non-volatile substance.
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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.
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.
What happens chemically when quicklime is added to water filled in a bucket?
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 type of reaction is represented by the following equation?
CaO + H2O → Ca(OH)
What type of chemical reaction take place when a magnesium wire is burnt in air?
Define a combination reaction.
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
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 ?
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
The chemical reaction between hydrogen and chlorine is a ................ reaction
Classify the following reaction as combination, decomposition, displacement, precipitation and neutralization. Also balance the equation.
\[\ce{CaCO3_{(s)} ->[heat]CaO_{(s)} + CO2_{(g)}}\]
What effect does an increase in concentration of H+ (aq.) in a solution have on the pH of solution?
Define: Chemical combination reaction
State why a direct combination reaction is called a – ‘synthesis reaction’.
Select the correct answer for the statement given below:
The product formed during direct combination reaction of carbon dioxide and water.
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?
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:
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")`
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.
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:
- Assertion: Rusting of Iron is endothermic in nature.
- Reason: As the reaction is slow, the release of heat is barely evident.
