The schools take the 10th-grade results into account when assigning the student to a certain stream in 11th grade. So, if you wish to pursue Science but did not receive enough marks in class 10, you may have to consider other possibilities. Many people find this intimidating, but Aakash tries to support you in your endeavour as much as possible. This class is very important for every student as their future somehow depends on the class 10 grades. Lakhmir Singh Solutions by the Aakash Institute for Class 10 Chemistry are available at the official Aakash website to assist students in understanding each concept.
The primary goal is to assist pupils in their academic endeavours. As a result, explanations are written in an easy-to-understand tone, making it easier for pupils to absorb more information. Experts and senior teachers with years of expertise produce the Lakhmir Singh Solutions for Class 10 Chemistry. Each answer includes a step-by-step overview and explanation of each topic and sub-subject, which will assist students in resolving the majority of their questions. Thus, the solutions try to synchronise with the pupils' intelligence. It also includes a follow-up and in-depth study of each question, allowing students to grasp the subject's basic concept and prepare them to tackle a single issue in various ways. After a comprehensive examination of the present curriculum, the answers are created to align with the students' intelligence.
Aakash gives free Solutions for Lakhmir Singh for Class 10 Chemistry, which is of great use to students. After going through the subject material in the book, we propose that students download the PDF file and read it fully. This will guarantee that you have a thorough knowledge of the topic.
If we talk about change, it can be classified into two categories, i.e., physical change and chemical change. Physical change is reversible, but chemical change cannot be reversed. In this chapter, the students get to learn about the chemical reactions that happen during chemical changes. Reactants participate in the reaction and are on the left-hand side of a chemical reaction, and the new substance obtained is known as a product. We will also get to know about various characteristics of the chemical reactions. These characteristics help us in finding out whether the chemical reaction has taken place or not.
The chapter also teaches us about the chemical equation, their types, and how they are worked out. A chemical equation is the presentation of the chemical reactions using formulae and symbols of substances. There are two types of chemical equations, i.e., balanced chemical equation and unbalanced chemical equation. A chemical equation can be loaded with more information by writing symbols for the physical states of compounds and the conditions in which reactions occur.
We will learn about chemical reactions and their various types. Chemical Reaction is the transformation of a chemical substance to another chemical substance. Types of chemical reactions include combination reaction, decomposition reaction, displacement reaction, double decomposition reaction, precipitation reaction, neutralisation reaction, oxidation and reduction reactions, and exothermic and endothermic reactions.
A decomposition reaction is further classified into three types, i.e., thermal decomposition, photodecomposition reaction, and electrolytic decomposition. In the oxidation and reduction reactions, various agents involved in carrying out the reactions are oxidising agents and reducing agents. Oxidising agents are those that give oxygen for oxidation or remove hydrogen; conversely, we have reducing agents that provide hydrogen for the reduction or removal of oxygen.
The textbook mentions various day-to-day examples of chemical reactions like corrosion and rancidity. Corrosion is an undesirable change in metals when they are attacked by moisture, air, acids, and bases. Rancidity is an undesirable change in oil- containing food items due to the oxidation of fatty acids. Adding antioxidants can prevent the food materials from going rancid. Similar results can be obtained by storing food in an airtight container, flushing out air with nitrogen gas, and refrigeration.
It also tells us about several types of corrosion and how we are supposed to prevent it. The types include rusting, corrosion of copper, and corrosion of silver metal. Corrosion weakens and shortens the life of iron and steel materials and systems such as railings, car frames, bridges, and cars. Painting, greasing and oiling, and galvanisation are effective methods for preventing rust.
The chapter starts by talking about the indicators. Indicators are compounds that change colour to signify whether a solution is acidic or basic. There are various types of indicators available. Here a few types of indicators have been discussed. Natural Indicators are indicators derived from natural sources. Litmus, turmeric, red cabbage, China rose, and other natural markers are commonly used to determine whether a product is acidic or basic. Olfactory Indicators are substances that change their scent when combined with acid or base—for instance, onion, vanilla, etc. Finally, synthetic indicators are produced in a laboratory—for instance, phenolphthalein, methyl orange, etc.
The chapter talks about acids, their types, various properties of acids, and various chemical reactions. For example, acids have a sour flavour, make blue litmus red, and dissolve in water to release hydrogen ions. Sulphuric acid, acetic acid, nitric acid, and other acids are examples.
Natural acids and Mineral acids are the two groups of acids that are classified based on their occurrence. Chemical properties of the acid include the reaction of acids with metal, the reaction of an acid with metal carbonate, and the reaction of acids with metal hydrogen carbonate. Tests for the evolution of various gases like carbon dioxide and hydrogen are also performed. Acids are also classified as weak acids and strong acids.
The chapter also discusses bases, their forms, different properties, and the various chemical reactions involved. Bases have a bitter taste, a soapy feel, make red litmus blue, and produce hydroxide ions in water. Sodium hydroxide (caustic soda), calcium hydroxide, and potassium hydroxide are other examples (caustic potash). Water-soluble and water-insoluble bases are the two kinds of bases. Alkali and alkaline earth metal hydroxides are water-soluble. Alkali is another name for these substances. Sodium hydroxide, magnesium hydroxide, calcium hydroxide, among others, are examples. Bases have several chemical properties like the reaction of bases with metals, the reaction of bases with oxides of non-metals, neutralisation reaction, and the reaction of metal oxide(base) with acids.
During an acid-base reaction, the acid's hydrogen ion joins with the base's hydroxide ion to form water. Both nullify each other when these ions combine and form water along with a subsequent salt. The textbook also discusses the dilution of acid and base as well as their strengths.
Only the acidity or basicity of a sample solution can be identified using litmus paper, phenolphthalein, methyl orange, and other markers, but these indicators do not indicate acid or base strength. As a result, a universal indicator is used to determine the intensity and the acidic and base quality of a given solution.
The chapter also focuses slightly on the topic of salts. Salts are ionic compounds that result when an acid and a base react to neutralise each other. Salts have no electrical charge. There are several different types of salts, but sodium chloride, ammonium chloride are among the most common. There are various kinds of salts present, like acid salts, basic salts, and neutral salts. Properties, uses and chemical reactions of some important chemical compounds are also discussed in this chapter, like Sodium Chloride (common salt), Bleaching powder, baking soda, and Washing soda.
The last topic discussed is the water of crystallisation. Hydrated salts are any salts that contain water molecules. Therefore, the water of crystallisation refers to the water molecule contained in salt.
Positive ions generate when metals lose electrons. As a result, metals are called Electropositive elements. The chapter also talks about the differences between metals and non-metals. Iron (Fe), Aluminium (Al), Silver (Ag), Copper (Cu), Gold (Au), and Platinum (Pt) are examples of metals and Carbon, chlorine and oxygen are some non- metallic elements.
The chapter states various physical properties and chemical properties of the metals. Physical properties in metals involve hardness, strength, conduction, malleability, ductility, etc. Chemical properties of metal involve reaction with oxygen, reaction with water, reaction with dilute acid, etc., leading to a certain product category.
Metal oxides have also been discussed in this chapter. The nature of metal oxide is basic. The reaction of metal oxides with water, the reaction of metals with the solution of other metal salts, and the reaction of two metal oxides (zinc oxide and aluminium oxide) are discussed under the chemical properties of metal oxides.
The Reactivity Series is the order of metal intensity or reactivity. When we are sliding from top to bottom in the reactivity sequence, the reactivity of elements reduces. Copper, gold, and silver are at the bottom of the reactivity scale, and therefore the least reactive. Noble metals are the metals that fall under this category. The most reactive element is potassium, which is at the top of the series.
Furthermore, in the chapter, we have non-metals, their properties. Non-metals are those elements that can neither be used to conduct electricity nor are ductile in nature. Non- metals are the elements that form negative ions by gaining an electron. Thus, non- metals are also known as Electronegative Elements—examples: Carbon (C), Sulphur (S), Phosphorous (P), etc.
The physical and chemical properties of non-metals are also discussed in this chapter. The physical properties of non-metals include insulators, dull in appearance, low density, low melting points, brittle etc. The chemical properties of non-metals include oxidising nature, electronegative nature and acidic oxides etc.
One of the most important topics discussed in this book is the occurrence and the extraction of metal. Minerals, ores, extraction of low-reactivity metals, extraction of medium-reactivity metals, extraction of high-reactivity metals, metal recycling or purification, and corrosion are the sub-topics discussed under this topic.
Minerals are compounds that are found in nature that have a consistent structure. Metals can be found in the crust of the Earth and seawater in the form of ores. Metal comes mostly from the Earth's surface. However, some salts, such as sodium chloride and magnesium chloride, are found in seawater. Ores are the rocks from which a metal can be mined profitably. The three important steps that are necessary for the extraction of metal from its ore are:
This chapter also teaches us about alloys. Alloys are a mixture of similar kinds of metals and non-metals. The properties of alloys include stronger than metals they are obtained from, and they are more corrosion resistant, the melting points for them are lower than the constituent metals, etc.
Topics like corrosion and its prevention are also discussed in this chapter. The majority of metals continue to react with the ambient air. As a result, a crust forms on top of the metal. Over time, the underlying coating of metal is destroyed due to conversion into oxides, sulfides, carbonate, and other compounds. As a consequence, the metal becomes corroded. Rust can be efficiently warded off by painting, greasing and oiling, and galvanisation.
In this chapter, we will talk about Carbon and its compounds. Compounds of Carbon contain covalent bonds. The covalent bond is formed by the mutual sharing of electron pairs between two atoms in a molecule. The atomic number of carbons is 6, which states that it is tough for it to gain or lose a large amount of atoms as if it does so, the compound will become unstable.
Hydrogen has 1 electron in its k shell, so it shares it with another atom of hydrogen and forms a single covalent bond. Oxygen has 6 electrons in the last shell. It needs 2 more electrons, forming a double bond with another oxygen atom to form an oxygen molecule. Similarly, Nitrogen has 5 electrons in its l shell. It requires 3 more electrons, so it shares it with other nitrogen atoms and forms the triple bond.
We will talk about the allotropes of Carbon in this chapter, and it has 3 allotropes-
First is the diamond, in which each Carbon is bonded with 4 other carbon atoms forming a 3-D structure. It is the hardest substance with a high melting point, and it is a bad conductor of electricity. Diamonds are used for jewellery.
The second is Graphite. It forms a hexagonal ring in which each carbon atom is bonded with 3 other carbon atoms. It is used to make pencils lead. The graphite structure allows it to have free electrons, which makes it a good conductor of electricity. Graphite can also be used as a dry lubricant.
The third is Fullerene. It is a football-shaped compound consisting of 60 carbon atoms arranged in 12 pentagons and 20 hexagons.
Carbon is said to be a versatile element in compound formation because of its catenation and tetravalent nature. Carbon has a one-of-a-kind ability to form covalent bonds with other carbon atoms, allowing it to form massive molecules. Catenation is defined as the phenomenon when an element forms long chains with other atoms of itself. Tetravalency is the ability to share electrons with 4 atoms at once. Also, Carbon exhibits high catenation property due to the small size of its atom.
The compounds of Carbon and Hydrogen are called hydrocarbons. Hydrocarbons that have a carbon-carbon single bond are called saturated hydrocarbons, also known as alkanes. Hydrocarbons which have double carbon bond or triple carbon bond are called Unsaturated Hydrocarbons. Hydrocarbons with a double bond are also called alkenes, and Hydrocarbons with a triple bond are called alkynes.
Isomers are molecules with the same molecular composition but different physical or chemical properties. Structural isomers are compounds with the same molecular formula but different shapes.
In this section, we will learn about the Homologous sequence. Homologous sequence refers to a group of organic compounds that share the same functional structure and similar chemical properties but differ by one CH 2 unit or 14 mass units.
In every homologous series, the successive members generally differ by one CH 2 unit or 14 mass units in a homologous sequence of compounds with the same functional group. Furthermore, due to the addition of the same functional group in the chain, all homologous sequence compounds have identical chemical properties. All these points fall under the category of the homologous series.
This chapter discusses the need for the classification of elements, how we are supposed to do it, and the importance of the periodic classification of elements.
It is tough to examine a large number of elements separately and understand their characteristics and applications. As a result, they have been divided into groups based on their shared characteristics. To comprehend the attributes of a large number of components collected in a group, categorisation is required.
There have been many attempts and theories to classify the elements by various people. Some of them have been discussed in this chapter. The first one is the Dobereiner's Triads. The atomic mass of the middle element in the triads was roughly the average of the atomic masses of the other two elements. The three elements in a triad were listed in order of increasing atomic masses. However, the triads came with few limitations, like Dobereiner was able to form only three triads from all the elements known at that time. He could not arrange all the known elements in the form of triads, even the elements having similar properties.
The second attempt to classify the elements was taken by Newland, known as Newland's Law of Octaves. This new rule also contained few limitations, which are as follows:
Newland's Law of Octaves was only valid up to calcium since, beyond then, no eighth element had qualities that were identical to the first. The properties of subsequently discovered elements did not fit within the Law of Octaves. Newlands had to alter two items in the same slot in a few situations to fit them into his table. He also placed things that had opposing characteristics in the same position.
The most successful periodic table obtained before the one in use currently was Mendeleev's periodic table. According to this theory, elements' physical and chemical characteristics are periodic functions of their atomic masses. Mendeleev's Periodic Law is the name given to this hypothesis. Although this method of classification was very good, it was also not foolproof. It also contains some limitations like no fixed position could be given to hydrogen. This table did not explain the position of isotopes, and in a few cases, the trend of increasing atomic masses was not followed.
Now comes the modern periodic table in the picture. This new form of the periodic table is based on the Modern Period Law, which states that "The physical and chemical properties of elements are the periodic function of their atomic numbers." Thus, in this table, all of the elements are listed in order of increasing atomic number.
The modern periodic table also comes with few limitations, which are as follows:
The position of hydrogen is fixed as it is kept in the group with the elements of the same valence electrons. The new form of periodic table arranges elements in the increasing order of their atomic number, so a clear difference between isobars like cobalt and nickel can be made. Since every element gets one spot and all isotopes have the same atomic number, they could be placed under one spot. The topics like valency, metallic and non-metallic character of the element are also discussed in this chapter.
Ques 1: Why is Lakhmir Singh Chemistry considered an important book for class 10 th chemistry?
The textbook by Lakhmir Singh has extensive subject material and a lot of questions. It teaches the concepts and clarifies the doubts that can arise while tackling various types of questions, and there the Aakash Institute has your back by providing the best solution to the questions.
Ques 2: Where can someone find the Lakhmir Singh Solutions, and how much does it cost?
The Lakhmir Singh solutions for class 10 th chemistry are available on the official website of the Aakash Institute. The solutions’ PDF is provided free of cost, and that makes it affordable to everyone.