CAPF (AC) 2023 (Paper-1) (Questions 51-100)

Distillation :- it is used for the separation of components of a mixture containing two miscible liquids that boil without decomposition and have sufficient difference in their boiling points. To separate a mixture of two or more miscible liquids for which the difference in boiling points is less than 25 K, fractional distillation process is used.

Alloys:- Alloys are mixtures of two or more metals or a metal and a non-metal and cannot be separated into their components by physical methods. But still, an alloy is considered as a mixture because it shows the properties of its constituents and can have variable composition. For example, brass is a mixture of approximately 30% zinc and 70% copper.

The element carbon occurs in different forms in nature with widely varying physical properties. Both diamond and graphite are formed by carbon atoms; the difference lies in the manner in which the carbon atoms are bonded to one another. In diamond, each carbon atom is bonded to four other carbon atoms forming a rigid three-dimensional structure.

In graphite, each carbon atom is bonded to three other carbon atoms in the same plane giving a hexagonal array. One of these bonds is a double-bond, and thus the valency of carbon is satisfied. Graphite structure is formed by the hexagonal arrays being placed in layers one above the other.

These two different structures result in diamond and graphite having very different physical properties even though their chemical properties are the same. Diamond is the hardest substance known while graphite is smooth and slippery.

Graphite is also a very good conductor of electricity unlike other non-metals that you studied in the previous Chapter. Diamonds can be synthesised by subjecting pure carbon to very high pressure and temperature.

These synthetic diamonds are small but are otherwise indistinguishable from natural diamonds. Fullerenes form another class of carbon allotropes. The first one to be identified was C-60 which has carbon atoms arranged in the shape of a football. Since this looked like the geodesic dome designed by the US architect Buckminster Fuller, the molecule was named fullerene.

When dilute sulfuric acid is poured on zinc granules, the acid is displaced by zinc, which is more reactive than hydrogen, resulting in zinc sulfate and hydrogen gas. It is a single displacement reaction of a non-metal by a metal.

Hydrogen, the most abundant element in the universe, is a versatile and clean energy carrier that can play a pivotal role in addressing global energy challenges. With its potential to replace fossil fuels, hydrogen is hailed as the fuel of the future. However, not all hydrogen is created equally, it comes in various forms, or "colors," based on its production methods and environmental impact.

An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, or sodium chloride (NaCl), in water would be represented as Na⁺ (aq) + Cl⁻ (aq).

Radha Krishna Commission was established to investigate the situation of Indian university education and make recommendations for improvements. Dr. Sarvepalli Radhakrishnan was named Chairman of the Commission on University Education. After India attained independence on August 15, 1947, the University Education Commission requested Dr. Radhakrishnan to serve as its chair.

• Aitchison Commission (1886): This commission was appointed under the chairmanship of Sir Charles Aitchison. Its primary objective was to review the working of the Public Service Commission (formed in 1886) and to propose schemes for the reorganization of the services.
  It recommended the abolition of the statutory civil service and the creation of provincial civil services, emphasizing the need for increasing the employment of Indians in public services. Thus, it was directly associated with public services.
• Islington Commission (1912): Chaired by Lord Islington, this commission examined the conditions of service, salaries, and prospects of government servants in India.
  It specifically looked into recruitment methods and advocated for holding simultaneous examinations for the Indian Civil Service in England and India, addressing issues of racial discrimination in pay and prospects. This commission was also clearly linked to public services.
• Lee Commission (1923): Headed by Lord Lee of Fareham, the Royal Commission on Public Services in India (Lee Commission) reviewed the structure and conditions of the Indian Civil Service and other superior services.
  It recommended measures for the future recruitment of both Europeans and Indians, the division of services into All-India Services and Central Services, and improvements in the terms of service for existing members. It was definitively associated with public services.

Gopal Hari Deshmukh (1823-1892), also known as Lokhitwadi, was a prominent social reformer, writer, and judge in 19th-century Maharashtra. He advocated for rational approaches to religion and societal reform, challenging harmful practices like caste discrimination, child marriage, and the dowry system.

He emphasized the need for women’s emancipation and education, contributing to various educational and social initiatives, including founding libraries in Pune and supporting the University of Bombay.

In addition to his efforts in Maharashtra, Deshmukh played a key role in social reforms in Gujarat, establishing the Gujarati Prarthana Samaj and the Gujarati Remarriage Society. His extensive literary work, including the influential collection "Lokhitwadikrta Nibandha Sangraha," helped pave the way for future reformist movements across India.

Valentine Chirol has collected and republished his valuable series of articles in The Times upon Indian unrest is an important and very instructive contribution to the study of what is probably the most arduous problem in the politics of our far-reaching Empire.

Annie Besant was a British social reformer and activist whose work left an indelible mark on Indian history. Renowned for her leadership in the Theosophical Society, Besant played a pivotal role in the revival of theosophy.

Her efforts in education played a significant role in establishing many educational institutions in India, including those
focused on women’s education.

Annie Besant passionately advocated for Indian self-rule, becoming a key figure in the Home Rule Movement. Her involvement also included presiding over the Indian National Congress session in 1917. Her leadership and dedication to India’s cause contributed to the broader struggle for independence.

In order to identify centres of craft production, archaeologists usually look for the following: raw material such as stone nodules, whole shells, copper ore; tools; unfinished objects; rejects and waste material.

In fact, waste is one of the best indicators of craft work. For instance, if shell or stone is cut to make objects, then pieces of these materials will be discarded as waste at the place of production.