Some chromosomal conditions are caused by changes in the number of chromosomes. These changes are not inherited, but occur as random events during the formation of reproductive cells (eggs and sperm). An error in cell division called nondisjunction results in reproductive cells with an abnormal number of chromosomes. Some chromosomal abnormalities occur when there is an extra chromosome, while others occur when a section of a chromosome is deleted or duplicated. Examples of chromosomal abnormalities include Down syndrome, Trisomy 18, Trisomy 13, Klinefelter syndrome, XYY syndrome, Turner syndrome and triple X syndrome.

Branding can be defined as name, term, sign, symbol or design or a combination of them which is intended to identify and distinguish the product of one firm with other. It is the means that differentiates products of one producer with competitors.

The Harappan Civilisation has its earliest roots in cultures such as that of Mehrgarh, approximately 6000 BC. The two greatest cities, Mohenjo-daro and Harappa, emerged circa 2600 BC along the Indus River valley in Punjab and Sindh. This work led to the the first excavations in the early 20th century at Harappa by Rai Bahadur Daya Ram Sahni, and by R.D. Banerji at another Indus Civilization city, Mohenjo Daro. Many scholars believe that the collapse of the Indus Valley Civilization was caused by climate change. Some experts believe the drying of the Saraswati River, which began around 1900 BCE, was the main cause for climate change, while others conclude that a great flood struck the area.

Nayakas were military chiefs usually mentioned law and order in their areas of control. They maintained forests and kept armed supporters. They use to control and expand fertile land and agricultural settlements. They usually submitted to kings (to the authority of Vijayanagara).

 The amara-nayaka system was a major political innovation of the Vijayanagara Empire. It is likely that many features of this system were derived from the Iqta system of the Delhi Sultanate. The amara-nayakas were military commanders who were given territories to govern by the raya

Eddy currents

• Eddy currents are induced currents in the body of conductor when subjected to changing magnetic flux.
• They are also known as Foucault current after the name of the scientist Foucault.
• They are known as eddy currents as they are in the pattern of eddiesin the water.
• Consider an electromagnet when attached to battery because of the current magnetic field will be produced which will induce current in the metallic plate.
• The current will be in the form of eddies.
• The metallic plate will be slightly drifted in the air because of eddy currents.

While British were leaving India after almost 200 years of ruling, Indian leadership had a large task in their hands: Uniting and Integrating a large of India into a single political unit. This problem was tremendous while dealing with Princely States. Though major part of British India was ruled by British directly still there were many princely states who were ruled by the British indirectly. With partition of India and Pakistan, India still had more than 500 smaller princely states which were not part of the two nations.

The problem in front of Indian leaders was twofold.

Of transforming the states into viable administrative units;
Of absorbing them into the constitutional units.
Challenges with Princely States were:

During the time of proclamation of India’s independence, Britain took a stand that princely states can either join with India or Pakistan or they can remain independent.
This clause created much confusion.
For the rulers of princely states they cannot even imagine of ceding their power under Indian constituent Assembly.
These states followed different administrative methods; some were aristocratic, strong differences between the states themselves, people with different opinions, mindsets and culture to name a few reasons.
Princely states started demanding independence after lapse of British paramountcy.
It was argued that after British withdrawal the situation in the Princely states would turn into lawlessness and anarchy and it is important to be associated with a centre of power to handle the situation.
Emergence of hundreds of independent states would made the struggle of Indian independence futile.
Therefore integration of princely states became a major agenda for Indian leaders.
Eventually, rulers of all the 652 states with exception of Junagarh, Kashmir and Hyderabad had signed the instrument of Accession by 15 August, 1947.
Junagadh Nawab wanted to join Pakistan but his people wanted to join Indian dominion.
Hyderabad wanted a sovereign status.
Kashmir had a Hindu prince and a Muslim majority population. The prince envisaged a sovereign status for the state and was reluctant to accede to either India or Pakistan.
The 3 major issues that impeded the integration process were, firstly their demand for independence, secondly the demand to integrate with Pakistan and finally the problems of administrative integration after political integration.
Also Pakistan was influencing the decisions of these states by offering financial as well political tools to these states if they acceded in Pakistan. This was a headache for Indian leadership.

A logo is a graphic mark, emblem, symbol or stylized name used to identify a company, organization, product, or brand. It may take the form of an abstract or figurative design, or it may present as a stylized version of the company's name if it has sufficient brand recognition. A logo is a name, mark, or symbol that represents an idea, organization, publication, or product. Typically, logos (such as the Nike "swoosh" and Apple Inc.'s apple with a bite missing) are uniquely designed for easy recognition. Logos are images, texts, shapes, or a combination of the three that depict the name and purpose of a business – to put it simply. However, a logo can and should be more than a symbol of identification. If designed well, it also tells a company's story, by conveying your brand message.

• Transition element:

1. A transition element is defined as the one which has incompletely filled d orbitals in its ground state or in any one of its oxidation states.
2. Zinc, cadmium, mercury are not regarded as transition metals due to completely filled d – orbital.

S-block elements are the elements with valence electrons in the s orbital. Elements in column 1 have one valence electron. Elements in column 2 have two valence electrons. S-block elements are very reactive. Elements in column 1 (the alkali metals) always lose their one valence electron to form a +1 ion. The p-block is the region of the periodic table that includes columns 3A to column 8A and does not include helium. There are 35 p-block elements, all of which are in p orbital with valence electrons. The p-block elements are a group of very diverse elements with a wide range of properties.

1. The electronic configuration for them are ns²np⁶

• Helium 1s ²2s²
• Neon 1s²,2s²,2p⁶
• Argon 1s²,2s²,2p⁶,3s²,3p⁶
• krypton1s²,2s²,2p⁶,3s²,3p64s²3d¹⁰4p6
• xenon 1s²,2s²,2p⁶,3s²,3p64s²3d¹⁰4p⁶4d¹⁰5s²5p⁶
• radon 1s²,2s²,2p⁶,3s²,3p64s²3d¹⁰4p⁶4d¹⁰5s²5p⁶4f¹⁴5d¹⁰6s²6p⁶

2.Atomic size : : It increases down the group as every time a new shell is added as we move down. They actually have Vander wall radii.

1. Ionization energy: They have highest ionization energy due to complete octet.
2. 4. Electron gain Enthalpy: It is positive as they have complete octet so they have no attraction for incoming electron.
3. Melting and boiling point: It is low due to weak force that exists that is Vander wall force.

Down the group size increases therefore Vander wall force also increases so as melting and boiling point increase.

1. All noble gases are odorless and colorless and tasteless.
2. All noble gases are sparingly soluble in water.
3. All are inert gases as they have complete octet.
4. All of them are monatomic.

The economic value of an obligation or debt that is payable by the enterprise to other establishment or individual is referred to liability. To put it in other words, liabilities are the obligations that are rising out of previous transactions, which is payable by the enterprise, through the assets possessed by the enterprise.

Example: Accounts payable, Interest payable, Deferred revenue etc.

1. The electronic configuration for them are ns²np⁶

• Helium 1s ²2s²
• Neon 1s²,2s²,2p⁶
• Argon 1s²,2s²,2p⁶,3s²,3p⁶
• krypton1s²,2s²,2p⁶,3s²,3p64s²3d¹⁰4p6
• xenon 1s²,2s²,2p⁶,3s²,3p64s²3d¹⁰4p⁶4d¹⁰5s²5p⁶
• radon 1s²,2s²,2p⁶,3s²,3p64s²3d¹⁰4p⁶4d¹⁰5s²5p⁶4f¹⁴5d¹⁰6s²6p⁶

The group 18 elements are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). These elements are non-reactive and are called noble gases as they have their outermost orbit complete. Due to stable electronic configuration they hardly react with other elements.

Preparation of Bleaching Powder

Bleaching powder is synthesized by the action of chlorine gas (produced from the chlor-alkali process) on dry slaked lime (Ca(OH)₂).

Ca(OH)₂ + Cl₂ → CaOCl₂ + H₂O

Uses of Bleaching Powder

• It is used for bleaching dirty clothes in the laundry, as a bleaching agent for cotton and linen in the textile industry.
• It is a strong oxidizing agent, hence used as an oxidizer in many industries.
• It is used as a disinfectant which is used for disinfecting water to make potable water.

Dry slaked lime with reacts with chlorine to prepare bleaching powder.

Cl₂ ​+ Ca(OH)_2​​⟶CaOCl₂​+CaCl₂​+HCl

     Dry slaked lime

The mixture is known as bleaching powder.

Properties of Chlorine:

• It is a greenish yellow gas with pungent and suffocating odour.
• It is soluble in H₂O

The word “electrolysis” was introduced by Michael Faraday in the 19th century. In chemistry, electrolysis is a method that uses a DC to drive a non-spontaneous chemical reaction. This technique is commercially significant as a stage in the separation of elements from naturally occurring sources such as ores using an electrolytic cell.

The process by which ionic substances are decomposed into simpler substances when an electric current is passed through them.

Deacon's process is a process used for preparation of molecular chlorine.

It involves the use of hydrogen chloride and oxygen as reactants and copper chloride as catalyst at high temperatures.

In this process, hydrogen chloride gas is oxidized by atmospheric oxygen in the presence of  CuCl₂ as catalyst at 723 K.

The balanced reaction for deacon's process is written as :

4HCl + O₂ →2Cl₂ + 2 H₂O

The reason F-F bond is weak is that when a fluorine tries to combine with another fluorine atom through a covalent bond, even though it has a very high electronegativity, since fluorine atom has a very small radius the electrons in the atoms repel each other and make the bond weak.