1.
Magnesium ribbon is rubbed before burning because it has a coating of
2.
Which of the following statements about the given reaction are correct? 3Fe+ 4H2O=Fe3O4+ 4H2
- Iron metal is getting oxidised
2. Water is getting reduced
3. Water is acting as reducing agent
4. Water is acting like an oxidising agent
3.
Three beakers labelled as A, B and C each containing 25 ml of water were taken. A small amount of NaOH, anhydrous CuSO4 and NaCl were added to the beakers A, B and C respectively. It was observed that there was an increase in the temperature of the solutions contained in beaker A and B, where as in beaker C the temperature of the solution falls. Which of the following statement(s) is (are) correct?
1. in beaker A and B exothermic process has occurred
2. in beaker A and B endothermic process occurred
3. in beaker C endothermic has occurred
4. in beaker C exothermic has occurred
4.
Give the ratio in which oxygen and hydrogen are present in water by volume
5.
Dissolving salt in water is an example of
6.
A substance which oxidises itself and reduces other is known as
7.
The reaction between lead nitrate and potassium iodide present in aqueous solutions is an example of
8.
Which of the following reaction is the combination of two elements
9.
In an electrolytic cell where electrolysis is carried, anode has
10.
A change is said to be a chemical change when
11.
Copper displaces which of the following metals from its salt solution
12.
Which of the following is an example of displacement reaction
13.
The reaction H2+ Cl2= HCl represents
14.
Which of the following equations is not balanced
15.
Which of the following reactions is not correct?
16.
Oxidation is a process of
17.
Aluminium oxide reacts with Sulphuric acid to form
19.
When hydrogen sulphide gas is passed through a blue solution of copper sulphate, a black precipitate of copper sulphide is obtained and the sulphuric acid so formed remains in the solution. The reaction is an example of
20.
Which of the following is not an example of decomposition reaction
21.
PbS reacts with ozone O3 and forms PbSO4. As per the balanced equation, molecules of ozone require for PbS is / are
22.
A student added dilute HCl to a test tube containing zinc granules and made the following observations
1) zinc surface became dull and black
2) a gas was evolved which is burnt with a pop sound
3) the solution remained colourless
23.
When carbon di oxide gas is passed through lime water
24.
Some crystals of copper sulphate were dissolved in water. the colour of the solution obtained would be
25.
Iron fillings were added to solution of copper sulphate. After 10 mintutes it was observed that the blue colour of the solution changed and a layer was deposited on iron fillings. The colour of the solution and coating would respectively be
26.
What happens when a copper rod is dipped in iron sulphate solution?
27.
Displacement reaction is
28.
All the methods mentioned below can be used to prevent the food from getting rancid except
1) storing the food in the moisture proof container
2) storing food in the refrigerator
3) keeping the food in the clean container
4) touching the food with clean hands
29.
When ferrous sulphate is heated strongly it undergoes decomposition to form ferric oxide as a main product accompanied by a change in colour from
30.
A chemical reaction does not involve
31.
Which among the following statement (s) is (are) true? Exposure of Silver chloride to sunlight for a long duration turns grey due to
-
Formation of Silver by decomposition of silver chloride
-
Decomposition of chlorine gas from silver chloride
-
Sublimation of silver chloride
-
Oxidation of chloride
32.
In the equation, NaOH + HNO3=NaNO3+ H2O Nitric acid acts as
33.
A dilute ferrous sulphate solution was gradually added to the beaker containing acidified permanganate solution. The light purple colour of the solution fades and finally disappears. Which of the following is the correct explanation for the following observations?
34.
In which of the following chemical equations, the abbreviations represent the correct states of the reactants and products involved at reaction temperature
35.
A red brown gas is eliminated along with oxygen and lead oxide. It is an example of
36.
PCl5+ xH2O=YH3PO4+ZHCl
The value of X, Y and Z are
37.
Colour of lead nitrate
38.
Colour of lead iodide
39.
Solution of the following is used for white washing
40.
On the wall a smooth coating of the following chemical if formed
41.
On heating green vitriol produces which of the pungent smelling gas
42.
A gas produced with brown fume is
43.
In the reaction of sulphuric acid and barium chloride the white precipitate is formed of
44.
Which one is not a thermal decomposition reaction?
45.
Rusting of iron involves a chemical reaction which is a combination of
46.
Which of the following reactions are neither oxidation nor reduction reaction?
47.
The displacement reaction between iron oxide (III) and a metal X is used for welding the railway tracks. Here X is
48.
Which of the following gases is used in the storage of fat and oil containing foods for a long time?
49.
The neutralization reaction between an acid and a base is a type of
50.
Decomposition reactions are
51.
Which of the following are exothermic processes?
1) reaction with water with quick lime
2) dilution of an acid
3) evaporation of water
4) sublimation of camphor
52.
The following reaction is an example of a
1. displacement reaction
2. combination reaction
3. redox reaction
4. neutralization reaction
NH4+O2=NO +H2O
53.
Which of the following information is not conveyed by chemical equation
54.
The following reaction is used in the lab to produce oxygen gas -
KClO4= KCl + O2
Which of the following statement is correct?
55.
Burning magnesium ribbon is brought in the gas jar of carbon di oxide. Which of the following is correct?
56.
In the double displacement reaction between aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate to form yellow precipitate?
57.
Which of the following reactions will not take place
58.
Rancidity is a process of
59.
The chemical used in cement industry is
60.
Fe is reacting with water to form
61.
CH3OH is formed when CO is reacting with
62.
The main component of natural gas is
63.
The reaction is used in black and white photography is
64.
On electric decomposition of acidulated water the anion is produced
65.
Black colour coating is formed on copper is
66.
The reaction between BaCl2 and NH4OH is
67.
The metal which is not corroded
68.
Curdy white precipitate is formed of
69.
After doing balancing the reaction of ammonia gas reacts with water to give ammonium hydroxide we get
70.
What is the physical state of FeSO4.H20
71.
In the reaction between Na and Cl2
72.
What is the colour of aqueous sodium sulphate solution
73.
The white barium sulphate is dissolved in
74.
A reddish element is obtained from the black coloured CuO on passing hydrogen is
75.
Which of the following is observed when water and quick lime are mixed
76.
MnO2+4HCl=MnCl2+ 2H2O + Cl2
The substance is oxidised is
77.
Marble is heated to produce
78.
On corrosion coatings are formed on silver and copper are respectively
80.
Chemical reactions are irreversible
