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Class 10 Chemistry Chapter 19 Nitrogen and Sulphur Test 7 | Full Unit
Class 10 Chemistry Chapter 19 Test 7 | Nitrogen & Sulphur
Prepare for the Punjab Board Class 10 Chemistry Examination 2027 with Chapter 19: Nitrogen and Sulphur – Class Test 7. This Full Unit Model Paper is part of our comprehensive Class 10 Chemistry Chapter-Wise Test Series, designed to help students revise important concepts and improve their examination performance. Based on the new syllabus issued by PECTAA Punjab, this test supports students preparing for the Punjab Board 2027 Model Papers. Practice Chemistry questions, evaluate your subject knowledge, strengthen your understanding of Nitrogen and Sulphur, and prepare confidently for your 10th Class annual examinations.
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PAPER NO.
07
CHEMISTRY
Chapter
Wise
Wise
Roll No.(in Figures):
(in Words):
NOTE:Four possible answers A, B, C and D to each question are given. The choice which you think is
correct, fill that circle in front of that question with Marker or Pen ink. Cutting or filling two or
more circles will result in zero mark in that question.
Q1.12
1.
The reason for maintaining higher temperature for the production of ammonia is:
(A) activation energy of the reaction is very high.
(B) activation energy of the reaction is very low.
(C) nitrogen and hydrogen are both gases.
(D) at low temperature nitrogen and hydrogen change into liquids.
2.
Haber process was discovered by:
(A) Robert Boyle
(B) Antoine Lavoisier
(C) F.J. Haber
(D) Jacques Charles
3.
The contact process used for the industrial production of H2SO4 is sensitive to the impurities present in SO2 and O2 because the impurities:
(A) affect the capability of the catalyst
(B) affect the purity of H2SO4
(C) do not let SO2 to react with oxygen
(D) decrease the rate of reaction appreciably
4.
Sulphuric acid is prepared in industry by:
(A) Haber process
(B) Contact process
(C) Solvay process
(D) Ostwald process
5.
Which of the following oxides is neutral in character?
(A) Al2O3
(B) SO2
(C) CO2
(D) NO
6.
Acidic oxides react with water to give:
(A) Bases
(B) Salts
(C) Acids
(D) Neutral solutions
7.
Secondary pollutants present in the atmosphere are:
(A) Oxides of nitrogen
(B) Oxides of Sulphur
(C) Ozone and PAN
(D) Oxides of Carbon
8.
Metals have tendency to lose electrons and form:
(A) Anions
(B) Neutral atoms
(C) Cations
(D) Molecules
9.
Oxides formed when oxygen reacts with metals:
(A) Acidic
(B) Basic
(C) Both basic and amphoteric
(D) Neutral
10.
Sodium and potassium react with dilute acids:
(A) Slowly
(B) Moderately
(C) Violently
(D) Do not react
11.
Major components of acid rain are:
(A) H2SO4 and HNO3
(B) H2SO3 and HNO2
(C) H2SO4 and HCl
(D) Acetic acid and HNO3
12.
VOCs stands for:
(A) Valuable Organic Compounds
(B) Volatile Organic Compounds
(C) Visible Organic Chemicals
(D) Various Oxidizing Compounds
Here is Subjective Part of Paper.
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Roll No.(in Figures):
(in Words):
Q2.Write short answers to any FIVE (5) questions:(5×2=10)
(i)How is nitrogen obtained from air?
Air is purified, compressed and cooled until it becomes liquid (about −200 °C). On fractional distillation, nitrogen (b.p. −196 °C) boils off first, while oxygen (b.p. −183 °C) stays behind as liquid.
(ii)Write the conditions used in Haber process.
Temperature about 450 °C, pressure 200–250 atm, and finely divided iron as catalyst: N2 + 3H2 ⇌ 2NH3.
(iii)How is hydrogen produced from methane?
Methane reacts with steam at high temperature (about 750–800 °C) over a nickel catalyst: CH4 + H2O → CO + 3H2. The CO is further reacted with steam: CO + H2O → CO2 + H2.
(iv)What happens to unreacted gases after ammonia is removed in Haber process?
The unreacted nitrogen and hydrogen are recycled back into the reaction chamber, so they are not wasted.
(v)Which conditions are used to oxidize SO2 to SO3?
Temperature about 450 °C, pressure 1–2 atm and vanadium pentoxide (V2O5) as catalyst: 2SO2 + O2 ⇌ 2SO3.
(vi)Why are SO2 and O2 purified before they react to produce SO3?
Impurities poison the V2O5 catalyst and reduce its efficiency, which lowers the rate and yield of the reaction.
(vii)Why CO2 is called an acidic oxide while CO is called a neutral oxide?
CO2 dissolves in water to form carbonic acid (H2CO3) and reacts with bases, so it is acidic. CO shows no reaction with water, acids or bases, so it is neutral.
(viii)Why is sulphuric acid called the king of chemicals?
It is used in making fertilizers, paints, detergents, plastics, fibres, batteries and many other chemicals, so it is the most widely used industrial chemical.
Q3.Write short answers to any FIVE (5) questions:(5×2=10)
(i)How do magnesium and calcium differ with each other towards their reactions with water?
Calcium reacts steadily with cold water to give Ca(OH)2 and H2. Magnesium reacts very slowly with cold water and readily only with steam, so calcium is more reactive.
(ii)What are oxides?
Oxides are binary compounds formed when oxygen combines with another element, e.g. MgO, CO2, SO2.
(iii)How are the reactivities of metals determined?
By observing how easily they react with oxygen, water and dilute acids, and by displacement reactions. Metals that lose electrons more easily are more reactive.
(iv)What are acidic oxides? Give examples.
Oxides of non-metals that react with water to form acids and with bases to form salts. Examples: CO2, SO2, SO3, N2O5.
(v)Which secondary pollutants are produced by oxides of nitrogen?
Ozone (O3) and PAN (peroxyacetyl nitrate), which form photochemical smog, along with nitric acid in acid rain.
(vi)What are amphoteric oxides? Give examples.
Oxides that show both acidic and basic behaviour, reacting with acids as well as bases. Examples: Al2O3, ZnO.
(vii)Why ammonia is regarded as an important chemical?
It is used to make fertilizers (urea, ammonium nitrate), nitric acid, explosives, cleaning agents and as a refrigerant.
(viii)What are metals?
Elements that tend to lose electrons and form positive ions (cations). They are generally shiny, malleable, ductile and good conductors of heat and electricity.
Q4.Write short answers to any FIVE (5) questions:(5×2=10)
(i)How SO2 present in the atmosphere is converted to SO3?
Atmospheric oxygen oxidizes SO2 in the presence of sunlight and dust particles acting as catalyst: 2SO2 + O2 → 2SO3. SO3 then dissolves in rain water to form H2SO4.
(ii)How do Group 1 and 2 metals react with cold water?
Group 1 metals react vigorously, forming hydroxides and hydrogen: 2Na + 2H2O → 2NaOH + H2. Group 2 metals react less vigorously (Mg very slowly, Ca steadily) to form hydroxides and hydrogen.
(iii)The burning of fossil fuels in a car engine is responsible for the production of oxides of nitrogen. Explain.
The very high temperature in the engine makes nitrogen and oxygen of air combine: N2 + O2 → 2NO. NO is then oxidized in air: 2NO + O2 → 2NO2.
(iv)Which metal will react with HCl fastly Zn or Fe?
Zinc reacts faster, because it is higher than iron in the reactivity series.
(v)The metals present at the top of the reactivity series are regarded as more reactive than those present at the bottom. Comment on this statement.
The statement is correct. Metals at the top lose electrons very easily, so they react vigorously with oxygen, water and acids. Metals at the bottom lose electrons with difficulty and are much less reactive.
(vi)Differentiate between primary and secondary pollutants.
Primary: released directly into the air (SO2, NO, CO). Secondary: formed in the atmosphere by reactions of primary pollutants (ozone, PAN, acid rain).
(vii)How fossil fuels produce SO2?
Fossil fuels contain sulphur compounds as impurities. On burning, the sulphur reacts with oxygen: S + O2 → SO2.
(viii)How do oxides of nitrogen form acid rain?
NO is oxidized to NO2, which dissolves in rain water with oxygen to form nitric acid: 4NO2 + O2 + 2H2O → 4HNO3. This falls as acid rain.
(PART – II)
Note: Attempt any TWO questions.(2 × 9 = 18)
Q5.(a)Explain the production of ammonia on industrial scale.5
Haber process: nitrogen (from liquid air) and hydrogen (from methane + steam) are mixed in 1 : 3 ratio, purified, compressed to 200–250 atm and passed over an iron catalyst at about 450 °C: N2 + 3H2 ⇌ 2NH3 (exothermic, about 15% yield per pass). The mixture is cooled so ammonia liquefies and is removed; unreacted N2 and H2 are recycled.
(b)Describe the contact process for the production of sulphuric acid.4
1) Sulphur or iron pyrites is burnt in air to give SO2. 2) SO2 and O2 are purified, then passed over V2O5 at about 450 °C and 1–2 atm: 2SO2 + O2 ⇌ 2SO3. 3) SO3 is absorbed in conc. H2SO4 to form oleum (H2S2O7). 4) Oleum is diluted with water to get concentrated H2SO4.
Q6.(a)Describe the role of oxides of nitrogen in the formation of PAN and the acid rain.5
PAN: NO2 splits in sunlight: NO2 → NO + O. The O atom forms ozone: O + O2 → O3. Ozone and NO2 react with volatile organic compounds (VOCs) to form PAN, a component of photochemical smog. Acid rain: NO2 dissolves in rain water with oxygen: 4NO2 + O2 + 2H2O → 4HNO3.
(b)Explain the formation and properties of acidic and basic oxides.4
Acidic oxides: non-metals burn in oxygen, e.g. S + O2 → SO2; they dissolve in water to give acids (SO2 + H2O → H2SO3) and react with bases to give salts. Basic oxides: metals burn in oxygen, e.g. 2Mg + O2 → 2MgO; those soluble in water give alkalis (Na2O + H2O → 2NaOH) and all react with acids to give salt and water.
Q7.(a)How nitrogen and hydrogen used in Haber process are obtained?5
Nitrogen: fractional distillation of liquid air. Hydrogen: from methane (natural gas) and steam over nickel catalyst at high temperature: CH4 + H2O → CO + 3H2, followed by CO + H2O → CO2 + H2.
(b)Write a note on the reactivity series of metals.4
The reactivity series arranges metals in decreasing order of reactivity: K, Na, Ca, Mg, Al, Zn, Fe, Pb, (H), Cu, Ag, Au. It is based on reactions with oxygen, water and dilute acids. A more reactive metal displaces a less reactive one from its salt solution; metals above hydrogen displace hydrogen from acids.
