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NCERT Solutions for Class 10 Science Chapter 1 Chemical Reactions and Equations

NCERT Solutions for Class 10 Science Chapter 1 Chemical Reactions and Equations

Edited By Irshad Anwar | Updated on Oct 07, 2023 09:12 PM IST

NCERT Solutions for Class 10 Science Chapter 1 Chemical Reactions and Equations

NCERT Solutions for Class 10 Science Chapter 1 Chemical Reactions and Equations: The solutions for class 10 science chapter 1 is a part of NCERT solutions for class 10 science. Here are the all NCERT Solutions for Class 10 Science Chapter 1 Chemical Reactions and Equations. Students appearing in the board exams must go through the Class 10 Science Chapter 1 NCERT solutions. Chemical Reactions and Equations is one of the most important chapters in the NCERT Books for Class 10 Science. All the questions with detailed explanations are provided in the Chemical Reactions and Equations Class 10 Solutions. NCERT Solutions for Class 10 Science "chemical reaction and equation" will help you in board exam preparation as well as competitive exam preparation. Go through the questions and answers given in NCERT Solutions for Class 10 Science Chapter 1.

Chemistry class 10 chapter 1 Science mainly deals with writing chemical equations and balancing chemical equations. The Chapter-wise NCERT Solutions for Class 10 science have been updated as per the latest CBSE Science class 10 syllabus and guidelines. In order for students to achieve the highest possible marks on the CBSE exams, the language used in chapter 1 science class 10 Solutions is simple to understand. Also, in class 10 science chapter 1 question answer students gain a basic understanding of chemical processes, including their types and the effects of chemical oxidation in daily life.

NCERT Solutions for Class 10 Science Chapter 1 Chemical Reactions and Equations

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Answers to NCERT Class 10 Science Chapter 1 – Chemical Reactions and Equations (Intext Questions and exercise)

Class 10th Science Chapter 1 Question Answer

Topic 1.1 Chemical equations:

Q 1 . Why should a magnesium ribbon be cleaned before burning in air?

Answer:

Magnesium is a very reactive metal so it reacts with oxygen to form a layer of magnesium oxide on its surface.

This layer is stable oxide so prevent further reaction of magnesium with oxygen. To remove this layer a magnesium ribbon is cleaned using sandpaper before burning in air.

Q 2. (i) Write the balanced equation for the following chemical reactions.

Hydrogen + Chlorine → Hydrogen chloride

Answer :

The balanced equation for the following chemical reactions is given as :

H_2(g)+Cl_2(g)\rightarrow 2HCl(g)

Q 2. (ii) Write the balanced equation for the following chemical reactions.

Barium chloride + Aluminium sulphate → Barium sulphate + Aluminium chloride

Answer:

The balanced equation for the following chemical reactions is given as :

3BaCl_2(s)+Al_2(SO_4)_3(g)\rightarrow 3BaSO_4(s)+2AlCl_3(s)

Q2. (iii) Write the balanced equation for the following chemical reactions.

Sodium + Water → Sodium hydroxide + Hydrogen

Answer:

The balanced equation for the following chemical reactions is given as :

2Na(s)+2H_2O(l)\rightarrow 2NaOH(aq)+H_2(g)

Q 3. (i) Write a balanced chemical equation with state symbols for the following reactions.

Solutions of barium chloride and sodium sulphate in water react to give insoluble barium sulphate and the solution of sodium chloride.

Answer:

The reaction of solutions of barium chloride and sodium sulphate in water react to give insoluble barium sulphate and the solution of sodium chloride is given by :

BaCl_2(aq)+Na_2SO_4(aq)\rightarrow BaSO_4(s)+2NaCl(aq)

Q 3. (ii) Write a balanced chemical equation with state symbols for the following reactions.

Sodium hydroxide solution (in water) reacts with a hydrochloric acid solution (in water) to produce sodium chloride solution and water.

Answer:

The reaction of sodium hydroxide solution (in water) reacts with a hydrochloric acid solution (in water) to produce sodium chloride solution and water is given by :

NaOH(aq)+HCl(aq)\rightarrow NaCl (aq)+H_2O(l)

Topic 1.2 Types of chemical reactions

Q 1. (i) A solution of a substance is used for whitewashing.

Name the substance ‘X’ and write its formula

Answer:

The substance ‘X’ is calcium oxide and its formula is CaO.

Q 1.(ii) A solution of a substance is used for whitewashing.

Write the reaction of the substance named in (i) above with water

Answer:

The reaction of calcium oxide with water is given by :

CaO(s)+H_2O(l)\rightarrow Ca(OH)_2

Q 2. Why is the amount of gas collected in one of the test tubes in Activity double of the amount collected in the other? Name this gas.

Answer :

Water contains one part oxygen and two parts hydrogen. During electrolysis, oxygen and hydrogen are produced in a 1:2 ratio. In electrolysis oxygen goes in one test tube and hydrogen in a second test tube, so the amount of gas collected in the second test tube is double of first one.

NCERT Textbook Solutions for Class 10th Science Chapter 1 Chemical Reaction and Equation


Topic 1.3 Have you observed the effects of an oxidation reaction in everyday life?

Q 1. Why does the colour of copper sulphate solution change when an iron nail is dipped in it?


Answer:

The color of copper sulphate solution change when an iron nail is dipped in it because iron displaces copper from copper sulphate forming iron sulphate,which is green.

CuSO_4(aq)+Fe(s)\rightarrow FeSO_4(aq)+Cu(s)

The colour change from blue to green.

Q 2. Give an example of a double displacement reaction other than the one given in Activity.

Answer:

An example of a double displacement reaction other than the one given in Activity is :

Na_2CO_3(aq)+CaCl_2(aq)\rightarrow CaCO_3(s)+2NaCl(aq)

Q 3.(i) Identify the substances that are oxidized and the substances that are reduced in the following reactions.

4Na(s)+O_{2}\rightarrow 2Na_{2}O(s)

Answer:

4Na(s)+O_{2}\rightarrow 2Na_{2}O(s)

In the above reaction, Na is oxidised and oxygen gets reduced.

Q 3.(ii) Identify the substances that are oxidized and the substances that are reduced in the following reactions.

CuO(s)+H_{2}(g)\rightarrow Cu(s)+H_{2}O(l)

Answer:

CuO(s)+H_{2}(g)\rightarrow Cu(s)+H_{2}O(l)

In the above reaction, CuO is reduced to form Cu and hydrogen gets oxidized to water.

NCERT Class 10 Science Chapter 1 Exercise Solutions

Q 1. Which of the statements about the reaction below are incorrect?

2PbO(s)+C(s)\rightarrow 2Pb(s)+CO_{2}(g)

(a) Lead is getting reduced.

(b) Carbon dioxide is getting oxidized.

(c) Carbon is getting oxidized.

(d) Lead oxide is getting reduced.


(i) (a) and (b)

(ii) (a) and (c)

(iii) (a), (b) and (c)

(iv) all

Answer:

2PbO(s)+C(s)\rightarrow 2Pb(s)+CO_{2}(g)

In the above reaction, PbO reduces to Pb and C(carbon) gets oxidized to carbon dioxide.

Hence, statements (a) and (b) are correct.

Thus, option (i) is correct.

Q 2. Fe_{2}O_{3}+2Al\rightarrow Al_{2}O_{3}+2Fe The above reaction is an example of a

(a) combination reaction.

(b) double displacement reaction.

(c) decomposition reaction.

(d) displacement reaction

Answer :

Fe_{2}O_{3}+2Al\rightarrow Al_{2}O_{3}+2Fe

The above reaction is an example of a displacement reaction.

Hence, option (d) is correct.

Q 3. What happens when dilute hydrochloric acid is added to iron filings? Tick the correct answer.

(a) Hydrogen gas and iron chloride are produced.

(b) Chlorine gas and iron hydroxide are produced.

(c) No reaction takes place.

(d) Iron salt and water are produced.

Answer:

When dilute hydrochloric acid is added to iron fillings then hydrogen gas and iron chloride are produced.

The reaction is given as :

Fe(s)+2HCl(aq)\rightarrow FeCl_2(aq)+H_2(g)

Thus, option (a) is correct.

Q 4. What is a balanced chemical equation? Why should chemical equations be balanced?

Answer:

The chemical equation which has an equal number of atoms of all elements on both sides of the reaction is known as a balanced chemical equation.

The law of conservation of mass states that mass can neither be created nor be destroyed so chemical equations should be balanced.

Q 5. (a) Translate the following statements into chemical equations and then balance them.

Hydrogen gas combines with nitrogen to form ammonia.

Answer:

Hydrogen gas combines with nitrogen to form ammonia can be written as :

3H_2(g)+N_2(g)\rightarrow 2NH_3

Q 5 (b) Hydrogen sulphide gas burns in air to give water and sulfur dioxide.

Answer:

Hydrogen sulphide gas burns in air to give water and sulfur dioxide can be written as :

2H_2S(g)+3O_2(g)\rightarrow 2SO_2(g)+2H_2O(l)

Q 5. (c) Barium chloride reacts with aluminum sulphate to give aluminum chloride and a precipitate of barium sulphate.

Answer:

Barium chloride reacts with aluminum sulphate to give aluminum chloride and a precipitate of barium sulphate can be written as :

3BaCl_2(aq)+Al_2(SO_4)_3(aq)\rightarrow 2AlCl_3(aq)+3BaSO_4(s)

Q 5. (d) Potassium metal reacts with water to give potassium hydroxide and hydrogen gas.

Answer:

Potassium metal reacts with water to give potassium hydroxide and hydrogen gas is given by :

2K(s)+2H_2O(l)\rightarrow 2KOH(aq)+H_2

Q 6. (a) Balance the following chemical equations.

Balance the following chemical equations. (a)

HNO_{3}+Ca(OH)_{2}\rightarrow Ca(NO_{3})_{2}+H_{2}O

Answer:

The balanced chemical equation is given as :

2HNO_{3}+Ca(OH)_{2}\rightarrow Ca(NO_{3})_{2}+2H_{2}O

Q 6. (b) Balance the following chemical equations.

NaOH + H_{2}SO_{4} \rightarrow Na_{2}SO_{4} + H_{2}O

Answer:

The balanced chemical equation is given as :

2NaOH + H_{2}SO_{4} \rightarrow Na_{2}SO_{4} + 2H_{2}O

Q 6. (c) Balance the following chemical equations.

NaCl+AgNO_{3}\rightarrow AgCl+NaNO_{3}

Answer:

The balanced chemical equation is given as :

NaCl+AgNO_{3}\rightarrow AgCl+NaNO_{3}

Q 6. (d) Balance the following chemical equations.

BaCl_{2}+H_{2}SO_{4}\rightarrow BaSO_{4}+HCl

Answer:

A balanced chemical equation is given as :

BaCl_{2}+H_{2}SO_{4}\rightarrow BaSO_{4}+2HCl

Q 7. (a) Write the balanced chemical equations for the following reactions.

(a) Calcium hydroxide + Carbon dioxide → Calcium carbonate + Water

Answer:

Calcium hydroxide + Carbon dioxide →Calcium carbonate + Water

The balanced chemical equations for the above reaction is given as :

Ca(OH)_2+CO_2\rightarrow CaCO_3+H_2O

Q 7. (b) Zinc + Silver nitrate → Zinc nitrate + Silver

Answer:

Zinc + Silver nitrate → Zinc nitrate + Silver

The balanced chemical equation for the above reaction is given as :

Zn+2AgNO_3\rightarrow Zn(NO_3)_2+2Ag

Q 7. (c) Aluminium + Copper chloride → Aluminium chloride + Copper

Answer:

Aluminium + Copper chloride → Aluminium chloride + Copper

The balanced chemical equation for the above reaction is given as :

2Al+3CuCl_2\rightarrow2 AlCl_2+3Cu

Q 7. (d) Barium chloride + Potassium sulphate → Barium sulphate + Potassium chloride

Answer:

Barium chloride + Potassium sulphate → Barium sulphate + Potassium chloride

The balanced chemical equation for the above reaction is given as :

BaCl_2+K_2SO_4\rightarrow BaSO_4+2KCl

Q 8. (a) Write the balanced chemical equation for the following and identify the type of reaction in each case.

(a) Potassium bromide(aq) + Barium iodide(aq) → Potassium iodide(aq) + Barium bromide(s)

Answer:

Potassium bromide(aq) + Barium iodide(aq) → Potassium iodide(aq) + Barium bromide(s)

The balanced chemical equation for the above reaction is given as :

2KBr(aq)+BaI_2(aq)\rightarrow 2KI(aq)+BaBr_2

It is a double displacement reaction.

Q 8. (b) Zinc carbonate(s) → Zinc oxide(s) + Carbon dioxide(g)

Answer:

Zinc carbonate(s) → Zinc oxide(s) + Carbon dioxide(g)

The balanced chemical equation for the above reaction is given by :

ZnCO_3(s)\rightarrow ZnO(s)+CO_2(g)

It is decomposition reaction.

Q 8. (c) Hydrogen(g) + Chlorine(g) → Hydrogen chloride(g)

Answer:

Hydrogen(g) + Chlorine(g) → Hydrogen chloride(g)

The balanced chemical equation for the above reaction is given by :

H_2(g)+Cl_2(g)\rightarrow 2HCl(g)

It is combination reaction.

Q 8. (d) Magnesium(s) + Hydrochloric acid(aq) → Magnesium chloride(aq) + Hydrogen(g)

Answer:

Magnesium(s) + Hydrochloric acid(aq) → Magnesium chloride(aq) + Hydrogen(g)

The balanced chemical equation for the above reaction is given by :

Mg(s)+2HCl(aq)\rightarrow MgCl_2(aq)+H_2(g)

It is displacement reaction.

Q 9. What does one mean by exothermic and endothermic reactions? Give examples.

Answer:

Exothermic reactions: Reactions in which heat is given out along with the products are called exothermic reactions.

Example : CH_4(g) + 2O_2 (g) \rightarrow CO_2 (g) + 2H_2O (g)

Endothermic reactions: Reactions in which energy is absorbed are known as endothermic reactions.

Example: The process of photosynthesis.

6CO_2 (g) +6H_2O(g)\rightarrow C_6H_1_2O_6(aq) + 6O_2 (g)

Q 10. Why is respiration considered an exothermic reaction? Explain .

Answer:

We know that energy is required to support life. We get energy from the food we eat.

The large molecules of food are broken into a simpler substance like glucose during digestion.

Glucose and oxygen react to provide energy to the body. This reaction is a combination reaction named as respiration. In this whole process, energy is released so respiration is considered an exothermic reaction.

C_6H_1_2O_6(aq)+6O_2\rightarrow 6CO_2(g)+6H_2O(l)+Energy

Q 11. Why are decomposition reactions called the opposite of combination reactions? Write equations for these reactions.

Answer:

In decomposition reactions, we can observe that a single reactant breaks down to give simpler products. This reaction source of energy. Whereas, in combination reaction two or more substances combine to give a product and energy is released in this reaction.

Hence, decomposition reactions called the opposite of combination reactions.

Example :

decomposition reaction : 2H_2O(l)\rightarrow 2H_2(g)+O_2(g)

and the combination reaction : 2H_2(g)+O_2(g)\rightarrow 2H_2O(l)+Energy

Q 12. Write one equation each for decomposition reactions where energy is supplied in the form of heat, light or electricity.

Answer:

The decomposition reaction by heat:

2FeSO_4(s)\rightarrow Fe_2O_3(s)+SO_2(g)+SO_3

The decomposition reaction by light :

2AgCl(s)\rightarrow 2Ag(s)+Cl_2(g)

The decomposition reaction by electricity :

2Al_2O_3(aq)\rightarrow 4Al(s)+3O_2(g)

Q 13. What is the difference between displacement and double displacement reactions? Write equations for these reactions.

Answer:

When an element displaces another element from its compound, a displacement reaction occurs.

Example : Fe(s) + CuSO_4(aq) \rightarrow FeSO_4(aq) + Cu(s)

Two different atoms or groups of atoms (ions) are exchanged in a double displacement reaction.

Example : Na_2SO_4(aq) + BaCl_2(aq) \rightarrow BaSO_4(s) + 2NaCl(aq)

Q 14. In the refining of silver, the recovery of silver from silver nitrate solution involved displacement by copper metal. Write down the reaction involved.

Answer:

In the refining of silver, the recovery of silver from silver nitrate solution involved displacement by copper metal. The reaction involved can be written as :

2AgNO_3(aq)+Cu(s)\rightarrow Cu(NO_3)_2(aq)+2Ag(s)

Q 15. What do you mean by a precipitation reaction? Explain by giving examples.

Answer:

Any reaction that produces a precipitate is called a precipitation reaction.

Example : Na_2CO_3(aq)+CaCl_2(aq)\rightarrow CaCO_3(s)+2NaCl(aq)

Here, we have CaCO_3 as precipitate so it is a precipitation reaction.

Q 16.







(a)


Explain the following in terms of gain or loss of oxygen with two examples each. (a) Oxidation







Oxidation is a reaction in which the gain of oxygen or loss of hydrogen can be observed.

Example : 2Cu + O_2 \rightarrow 2CuO

CO_2+H_2\rightarrow CO+H_2O

Q 16. (b) Reduction

Answer:

The reaction in which the loss of oxygen or gain of hydrogen can be observed is known as reduction reaction.

Example : CuO +H_2 \rightarrow Cu+H_2 O

ZnO + C\rightarrow Zn+ CO

Q 17. A shiny brown coloured element ‘X’ on heating in the air becomes black in colour. Name the element ‘X’ and the black coloured compound formed.

Answer:

A shiny brown colored element is copper (Cu) and on heating, in the air it becomes black in colour because of the formation of copper oxide(CuO).

2Cu+O_2\rightarrow 2CuO

Q 18. Why do we apply paint on iron articles?

Answer:

To prevent iron from rusting paint is applied to iron articles. After applying paint iron articles are not in contact with moisture and air and hence rusting is prevented.

Q 19. Oil and fat containing food items are flushed with nitrogen. Why?

Answer:

We know that nitrogen is an inert gas and does not react with the oil and fat-containing food. Whereas, other gases like oxygen react with the oil and fat-containing food and make them rancid. Hence, to remove oxygen and prevent food from acidity food items are flushed with nitrogen.

Q 20.(a) Explain the following terms with one example each.

Corrosion

Answer:

Corrosion is a process in which metals deteriorate due to chemical reaction with moisture, air, and chemicals. Rusting of iron is a major example of corrosion. Iron corrodes in the presence of moisture and air.

4Fe+3O_2+H_2O\rightarrow 2Fe_2O_3.H_2O

Q 20. (b) Rancidity

Answer:

(b) Rancidity

The process of oxidation of fats and oils which can be noticed by a change in color, smell, and taste is known as rancidity.

Example: When butter is kept in the open atmosphere than its smell and taste change which results in rancidity.






Chapter-Wise NCERT Solutions for Class 10 Science

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Science Class 10: Important Formulas and Diagrams + eBook link

Important Formulas from Chapter 1 Science Class 10 are listed below. Go through them to make your basic concept more concrete.

TYPES OF CHEMICAL REACTIONS

  1. Combination or Addition reaction: A + B → AB

  2. Decomposition Reaction: AB → A + B

  3. Displacement Reaction: A + BC → AC + B

  4. Double Displacement Reaction or Precipitation Reaction:

AgNO3 + NaCl → AgCl(s) + NaNO3

  1. Oxidation and Reduction reactions:

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For more, Download the - NCERT Class 10 Science: Chapterwise Important Formulas, Diagrams, And Points

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NCERT Solutions for Class 10 Science Chapter 1 Chemical Reactions and Equations - Topics and Subtopics

Important topics and subtopics from Science Class 10 Chapter 1 are given below:

  • Chemical reactions and equations
  • Chemical equations
  • Types of chemical equations
  • Effects of oxidation reactions in everyday life?

The NCERT Solutions for Class 10 Science Chapter 1 have good weightage, and there will be around four questions asked from this chapter every year. The types of questions that appear in chemical reaction and equation class 10 are mostly practice-based questions. Thorough knowledge and good practice will help learners score full marks on the questions asked in this chapter. Science Class 10 Chapter 1 NCERT Solutions are easy to access and download.

Benefits of NCERT Solutions for Class 10 Science Chapter 1 Chemical Reactions and Equations:

  • Through the Class 10 Science Chapter 1 question answer, you will also get to know why balancing between chemical equations is important.
  • The Class 10 Science Chapter 1 NCERT Solutions gives an overview of the main concepts mentioned in the chapter and helps you get well versed in important topics such as writing chemical equations and balancing them.
  • NCERT Solutions for Class 10 Science Chapter 1 PDF Download will be made available in a short time. Till then, you can save the webpage to practice the Science Class 10 Chapter 1 question answer offline.
  • These NCERT Class 10 Science Chapter 1 solutions are explained by the experts.

Highlights of NCERT Solutions for Class 10 Science Chapter 1: Chemical Reactions and Equations

The highlights for the Class 10 Science Chapter 1 solution PDF are given below:

  • The NCERT (CBSE) Syllabus and Books are strictly followed in the class 10 science chapter 1 question answer.
  • The Class 10 Chapter 1 Science are easy-to-understand and comprehensive
  • On this page, you will find clear and concise Chemical Reactions and Equations Class 10 questions answers.
  • The solutions given for chemical equation class 10 help clear doubt and give in-depth knowledge of concepts.
  • The NCERT Solutions Class 10 Science Chapter 1 are prepared by subject matter experts in the easiest possible way.
  • All the exercise questions and in-text solved questions are available for 10 grade science chapter 1.
  • Stepwise solutions are provided here for 10th Class science chapter 1.
  • Diagrams are provided wherever required for a better understanding in Science Class 10 Chapter 1 question answer
  • class 10 chemistry chapter 1 solutions will help you to score good marks in board exams.

How to Use NCERT Solutions for Class 10 Science Chapter 1 Chemical Reactions and Equations?

  • Firstly go through the Science Chapter 1 Class 10 and learn all the concepts. Afterwards, move to the NCERT Class 10 Science Solutions Chapter 1.

  • Practice all the diagrams, equations and definitions regularly to have a strong understanding of the Chapter 1 Science Class 10.

  • To check your preparation level, you can check previous year question papers from the Class 10 board exams and check if you are able to solve all the questions with the help of NCERT solutions.

  • If you have any questions that you are not able to find in the NCERT solutions for Class 10 Science Chapter 1, Well, go ahead and ask your question in the discuss doubts section. The experts will explain to you the solutions.

    NCERT Solutions for Class 10 for other subjects

  • NCERT Solutions for Class 10 Maths
  • Also Check NCERT Books and NCERT Syllabus here:

Frequently Asked Question (FAQs)

1. What are the important topics of Class 10 Science Chapter 1 Chemical Reactions and Equations?
  • Chemical equations

  • Writing a chemical equation

  • Balanced chemical equations

  • Types of chemical reactions

  • Effects of oxidation reactions in everyday life

2. How can I get the NCERT Class 10 Science solution offline?

NCERT Solutions for Class 10 Science Chapter 1 PDF Download is not available right now. But you can save the webpage to get the solutions offline.

3. What is the weightage of chapter Chemical Reactions and Equations in CBSE Class 10 board final exam?

Weightage of chapter Chemical Reactions and Equations in CBSE class 10 board final exam is around 5 marks. To solve questions refer to NCERT book and NCERT exemplar. Also refer to CBSE previous year papers of Class 10 CBSE board.

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Get answers from students and experts

A block of mass 0.50 kg is moving with a speed of 2.00 ms-1 on a smooth surface. It strikes another mass of 1.00 kg and then they move together as a single body. The energy loss during the collision is

Option 1)

0.34\; J

Option 2)

0.16\; J

Option 3)

1.00\; J

Option 4)

0.67\; J

A person trying to lose weight by burning fat lifts a mass of 10 kg upto a height of 1 m 1000 times.  Assume that the potential energy lost each time he lowers the mass is dissipated.  How much fat will he use up considering the work done only when the weight is lifted up ?  Fat supplies 3.8×107 J of energy per kg which is converted to mechanical energy with a 20% efficiency rate.  Take g = 9.8 ms−2 :

Option 1)

2.45×10−3 kg

Option 2)

 6.45×10−3 kg

Option 3)

 9.89×10−3 kg

Option 4)

12.89×10−3 kg

 

An athlete in the olympic games covers a distance of 100 m in 10 s. His kinetic energy can be estimated to be in the range

Option 1)

2,000 \; J - 5,000\; J

Option 2)

200 \, \, J - 500 \, \, J

Option 3)

2\times 10^{5}J-3\times 10^{5}J

Option 4)

20,000 \, \, J - 50,000 \, \, J

A particle is projected at 600   to the horizontal with a kinetic energy K. The kinetic energy at the highest point

Option 1)

K/2\,

Option 2)

\; K\;

Option 3)

zero\;

Option 4)

K/4

In the reaction,

2Al_{(s)}+6HCL_{(aq)}\rightarrow 2Al^{3+}\, _{(aq)}+6Cl^{-}\, _{(aq)}+3H_{2(g)}

Option 1)

11.2\, L\, H_{2(g)}  at STP  is produced for every mole HCL_{(aq)}  consumed

Option 2)

6L\, HCl_{(aq)}  is consumed for ever 3L\, H_{2(g)}      produced

Option 3)

33.6 L\, H_{2(g)} is produced regardless of temperature and pressure for every mole Al that reacts

Option 4)

67.2\, L\, H_{2(g)} at STP is produced for every mole Al that reacts .

How many moles of magnesium phosphate, Mg_{3}(PO_{4})_{2} will contain 0.25 mole of oxygen atoms?

Option 1)

0.02

Option 2)

3.125 × 10-2

Option 3)

1.25 × 10-2

Option 4)

2.5 × 10-2

If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will

Option 1)

decrease twice

Option 2)

increase two fold

Option 3)

remain unchanged

Option 4)

be a function of the molecular mass of the substance.

With increase of temperature, which of these changes?

Option 1)

Molality

Option 2)

Weight fraction of solute

Option 3)

Fraction of solute present in water

Option 4)

Mole fraction.

Number of atoms in 558.5 gram Fe (at. wt.of Fe = 55.85 g mol-1) is

Option 1)

twice that in 60 g carbon

Option 2)

6.023 × 1022

Option 3)

half that in 8 g He

Option 4)

558.5 × 6.023 × 1023

A pulley of radius 2 m is rotated about its axis by a force F = (20t - 5t2) newton (where t is measured in seconds) applied tangentially. If the moment of inertia of the pulley about its axis of rotation is 10 kg m2 , the number of rotations made by the pulley before its direction of motion if reversed, is

Option 1)

less than 3

Option 2)

more than 3 but less than 6

Option 3)

more than 6 but less than 9

Option 4)

more than 9

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