Class 10 Chemical equations and reaction Test Paper
In this page we have Chemical reactions and equations class 10 test paper . Hope you like them and do not forget to like and share the page.
a. Multiple Choice Questions
b. One Mark questions
c. Short Answer type
d. Long answer questions
Multiple Choice Questions
Question 1. Which of the following equations represents a combination reaction?
(a) \(2H_2 + O_2 \rightarrow 2H_2O\)
(b) \(2HgO \rightarrow 2Hg + O_2\)
(c) \(Zn + CuSO_4 \rightarrow ZnSO_4 + Cu\)
(d) \(AgNO_3 + NaCl \rightarrow AgCl + NaNO_3\)
Question 2. Which of the following equations represents a decomposition reaction?
(a) \(2H_2 + O_2 \rightarrow 2H_2O\)
(b) \(2HgO \rightarrow 2Hg + O_2\)
(c) \(Zn + CuSO_4 \rightarrow ZnSO_4 + Cu\)
(d) \(AgNO_3 + NaCl \rightarrow AgCl + NaNO_3\)
Question 3. Which of the following equations represents a displacement reaction?
(a) \(2H_2 + O_2 \rightarrow 2H_2O\)
(b) \(2HgO \rightarrow 2Hg + O_2\)
(c) \(Zn + CuSO_4 \rightarrow ZnSO_4 + Cu\)
(d) None of these
Question 4.The following reaction is used for the preparation of oxygen gas in the laboratory
Which of the following statement(s) is(are) correct about the reaction?
(a) It is a decomposition reaction and endothermic in nature
(b) It is a combination reaction
(c) It is a decomposition reaction and accompanied by release of heat
(d) It is a photochemical decomposition reaction and exothermic in nature
Answer
1(a), 2(b), 3(c), 4(a)
One Marks Questions
Question 1. Identify physical or chemical changes in the following:
(a) A rock rolls down a slope
(b) Baking of cake
(c) Plucking of fruit
(d) Burning of L.P.G
(e) Cutting of carrots Question 2. Explain whether the addition of dilute sulphuric acid to iron is a physical or chemical change. Question 3. Heating of iodine crystals is considered to be a physical change. Explain. Question 4. Burning of a candle may be considered as showing physical and chemical changes occurring simultaneously. Explain.
Answer
(1)
(a) Physical change
(b) Chemical change
(c) Physical change
(d) Chemical change
(e) Physical change
(2) It is a chemical change as Iron react with dilute sulphuric acid to form Ferrous sulphate
(3) When iodine crystals are heated, the solid changes to the vapor state i.e., it sublimes. This is identified as a physical change since
(a) The vapors formed settle on the cooler parts of the test tube as solid - so the change is temporary and reversible.
(b) There is no change in mass.
(c) There is no energy (heat) change involved because the heat absorbed when the solid iodine changes to vapor, is given out when the vapor changes back to solid.
(d) The chemical composition of the solid is same as that of the vapor.
(4) When the candle burns, the heated wax melts. The melted wax re-solidifies and no new substance is formed, therefore this is a physical change. However, the wax and the wick continue to burn and produce new substances like carbon dioxide and water vapor. This burning process is a chemical change as it is a permanent change. Also, energy in the form of heat and light is evolved.
Short Answer Questions
Question 1. what is the ratio of number of moles of reactants to the number of moles of products in the equation.
H2S (g) + SO2 (g) -> S (s) + H2O (liq)
Answer
2H2S (g) + SO2 (g) -> 3S (s) + 2H2O (liq)
Ratio of number of moles of reactants to the number of moles of products= 3/5
Question 2. In the refining of silver, the recovery of silver from silver nitrate solution involved displacement by copper metal. Write down the reaction involves.
Answer
When copper is mixed in silver nitrate solution, it displaces the silver because copper is more reactive than silver.
2AgNO3 + Cu �> Cu(NO3)2 + 2Ag
Question 3.Translate the following statements into chemical equations and then balance them.
(a)Hydrogen gas combines with nitrogen to form ammonia
(b)Hydrogen sulphide gas burns in air to give water and sulfur dioxide.
(c)Barium chloride reacts with aluminum sulphate to give aluminum chloride and a precipitate of barium sulphate.
(d)Potassium metal reacts with water to give potassium hydroxide and hydrogen gas.
Question 5.Why is respiration considered as an exothermic reaction? Explain. Question 6.What is rancidity? Question 7.Write the balanced chemical equation of the following and identify the type of reaction in each case:
i.Potassium bromide (aq) + Barium iodide (s)
ii.Zinc carbonate (s) -> Zinc oxide (s) + Carbon dioxide (g)
iii.Magnesium (s) + hydrochloric acid (aq)->Magnesium chloride (aq) + Hydrogen (g)
Answer
(i) Double Displacement
2KBr+BaI2 -> 2KI + BaBr2
(ii) Decomposition
ZnCO3 -> ZnO + CO2
iii)Displacement
g + 2HCl -> MgCl2 + H2
Question 8.Balance the following chemical reaction:
(a)NH4NO3-> N2O + H2O
(b)P4O10 + H2O -> H3PO4
(c)HIO3 -> I2O5 + H2O
(d)As + Cl -> AsCl5
Question 9.Balance the chemical equations for the following important industrial processes:
(a)Molecular nitrogen and hydrogen combine to give ammonia.
(b)Molecular hydrogen and carbon monoxide react to form methanol (CH3OH).
(c)CaO + C ->CO + CaC2
(d)C2H4 + O2+ HCl -> C2H4Cl2 + H2O
Question 12.Represent each of the following word equations with a balanced chemical equation.
(a)Disilane gas (Si2H6) undergoes combustion to form solid silicon dioxide and water.
(b)Solid aluminum hydride is formed by a combination reaction of its two elements.
(c)When solid calcium bi sulfate is heated, it decomposes to solid calcium oxide, sulfur dioxide gas, and water. Question 13.A large piece of zinc metal is placed in a copper (II) sulfate, CuSO4, solution. The blue solution become colorless as copper metals falls to the bottom of the container. The resulting solution contains zinc sulfate, ZnSO4. Write balanced formula unit, total ionic, and net ionic equations for the reaction Question 14.A solution of AgNO3 is mixed with a solution of K2S. write the molecular, total ionic and net ionic equations illustrating the reaction. Question 15.Write decomposition reactions for the following compounds
(a)Ca(HCO3)2
(b)Ag2O
(c)N2O3 Question 16.Write one equation each for decompositions reactions where energy is supplied in the form of heat, light or electricity.
Answer
When Calcium Carbonate is heated, it decomposes to give calcium oxide and carbon dioxide :-
CaCO3 (s) -----Heat----> CaO (s) + CO2
When electric current is passed through H2O, it decomposes to give $H_2$ and $O_2$:-
2H2O (l) ----Electricity----> 2H2 (g) + O2 (g)
When silver chloride is exposed to light, it decomposes to form silver metal and chlorine gas:-
2AgCl (s) ----Light----> 2Ag (s) + Cl2 (g)
Long Answer Questions
Question 1.What do you understand by exothermic and endothermic reactions? Explain with one example each? Write a balanced chemical equation for the process of photosynthesis and the condition of the reaction giving physical state of all the substances? Question 2.Why decomposition reactions are called the opposite of combination reactions? Write equations for these reactions. Discuss the importance of decomposition reaction in metal industries with three points? Question 3.What do you mean by precipitation reactions? Explain by giving examples. Question 4.Illustrate an activity to show a double displacement reaction. Give the chemical equation of the reaction that takes place. Write the physical state of the product obtained? Question 5.Balance the following equations
(i)KClO3 -> KCl + O2
(ii)H2SO4 + NaOH -> Na2SO4 + H2O
(iii)H2O2 -> H2O + O2
(iv)Na2CO3 + HCl -> NaCl + NaHCO3
(v)Mg + N2 -> Mg3N2
(vi)Fe + H2O -> Fe3O4 +H2
(vii)MnO2 + Al -> Mn + Al2O3
(viii)Si2H6 + H2O -> Si(OH)4 + H2
(ix)NH3 + O2 -> NO + H2O
(x)B4H10 + O2 -> B2O3 + H2O
(xi)Al + CuCl2 -> AlCl3 + Cu
Question 6.The oxidation of iron to rust is a problem, but the oxidation of aluminum to aluminum oxide is not why? Question 7.Write balanced equations by predicting the products of the following reactions. Include the physical state of each element or compound.
(a)Phosphorus burn in chlorine to form phosphorus pentachloride.
(b)A single- displacement reaction of calcium metal with a nitric acid solution
(c)Burning of natural gas.
(d)The process of respiration.
(e)When a green iron salt is heated strongly, its color finally changes to black and odor of burning sulfur is given out.
Summary
This Chemical reactions and equations class 10 test is prepared keeping in mind the latest syllabus of CBSE . This has been designed in a way to improve the academic performance of the students. If you find mistakes , please do provide the feedback on the mail.
