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A material which is burnt to obtain heat is called a fuel. Since ethanol burns with a clear flame giving a lot of heat, therefore it is used as a fuel.

Some countries add ethanol to petrol to be used as a fuel in cars. Thus ethanolis used as an additive in petrol.

Ethanol alone can also be used as a fuel for cars.

ethanol is also known as ethyl alcohol. It is a volatile liquid having a low boiling point of 78°C (351 K).

Ethanol is appreciable as fuel because of the following reasons:

1) Ethanol burns with a clean flame giving a lot of heat, therefore it is used as fuel.

2) Ethanol has high calorific value and proper ignition temperature.

3) Ethanol is a clean fuel and do not left behind ash after burning.

When you mix vegetable oil with 20% NaOH in ethanol. The alkaline hydrolysis leads to formation of the sodium salt of the fatty acid. Boil this under reflux to speed up the reaction and move it to completion. Reflux stops volatile components from escaping. The ethanol content is removed by distillation. The residue left is excess NaOH, glycerol and soap dissolved in minimum hot water Once cooled, pour it into concentrated NaCl solution. Stir and allow it tocool as well. Glycerol and NaOH dissolve in brine. Soap does not dissolve in brine and forms a cake on top of the liquid. Water, brine and glycerol is removed by a vacuum filtration. Soap is rinsed with ice-cold water to reduced amount, lost by dissolving.

i) The German doctorRobert Kochis considered the founder of modern bacteriology. His discoveries made a significantcontributionto the development of the first 'magic bullets' - chemicals developed to attack specific bacteria - andKochwas awarded a Nobel Prize in 1905.

ii) Pasteur's scientific and medical accomplishments include cure forrabies, anthrax, chicken cholera, and silkworm diseases. He also contributed towards developing the first vaccines and provided logical grounds for fermentation and brewing.

Answer:(2)3FExplanation:In MnO4-, Mn has +7 oxidafion state.

While in MnO2, Mn has +4 oxidation state.

Hence conversion of +7 to +4.

Hence charge required = 3 F.

Water has a unique property of anomalous expansion. When water is cooled from room temperature it first contracts in volume and becomes increasingly dense as do other liquids, but at 4° C water reaches its maximum density. On further cooling, it starts expanding and become less dense. This will be continued till the temperature reaches 00C, the point at which it freezes into ice.This unusual property of water enables marine life to exist in the polar region where the temperature falls below freezing temperature. The outer layer of water becomes ice and floats over the water. As the water has the highest density at 40C sinks down.

The equation for Haber ammonia synthesis is: Take the reaction:2N2(g)+3H2(g)⇌2NH3(g)

On the left side of the equilibrium, there are 4 molecules (or moles) of N2 and H2, and on the right side there are only 2 molecules(or moles) of NH3. It is evident that the formation of ammonia is accompanied by a overall decrease in the number of molecules. Pressure is directly proportional to the number of molecules (moles), when other things remain the same..

Therefore, when pressure is increased, the system in equilibrium will tend to neutralise the effect by favouring the direction that is accompanied by a decrease in pressure or the number of molecules. That is, the equilibrium will be shifted towards the right to nullify the effect of increased pressure, as per Le Chatelier's principle.

Conversely, when the number moles of products are greater than that of reactants, increase in pressure will shift the equilibrium to the left. When the number of moles are equal on both sides, increase in pressure will have no effect on the equilibrium.

The reaction of calcium with water is less violent. SO, the heat released is not sufficient for the hydrogen to catch fire. Calcium starts floating because the bubbles of hydrogen gas which are formed during the reaction stick to the surface of the metal and hence caclium floats on water.

a)H3PO4, phosphoric acid, can be written O=P(OH)3. It has three acidic protons (attached to oxygen) and is therefore tribasic. Its salts are calledphosphates.

But H3PO3, phosphonic acid, has one of the hydrogens directly bound to phosphorus as O=PH(OH)2. This means that only two hydrogens are available to act as acids. Its salts are calledphosphonates.

There is also an H3PO3, phosphorous acid P(OH)3, thatistribasic. Its salts are calledphosphites.

b)In NCl3 it occurs on chlorine in PCl3, it occurs on phosphorus. Water oxidizes the chlorine during the reaction with NCl3 but not in case of PCl3. Fluorine gives ozonized oxygen with water on heating. With interhalogen compounds, the larger halogen will become the hypohalous acid

1

2

3

4

option 2

Ans :- Diazonium compounds or diazonium salts are a group of organic compounds sharing a common functional group R−N⁺ ₂X− where R can be any organic group, such as an alkyl or an aryl, and X is an inorganic or organic anion, such as a halogen.

Diazonium salts are made by taking an alkyl or aryl primary amine and reacting it with sodium nitrite in the presence of hydrochloric acid. Example reactions that diazonium salts take part in are: Sandmeyer reaction: synthesis of an aryl chloride by the action of copper (I) chloride.

option D.

1)Alpha hydrogen is nothing but the hydrogen atom attached to the alpha carbon atom,which in turn is attached to the carbonyl carbon. After removal of alpha hydrogen atom, conjugated base so obtained is resonance stabilised. Hence alpha hydrogen atoms in aldehydes and ketones are acidic in nature.

2)

3)In Benzoic acid there is -COOH group on benzene which is meta directing in nature.

All the metadirecting groups exert strong -I along with the -M effect which decrease the electron density from the benzene ring and make it less reactive for friedel crafts reaction.

Ethane undergo substitution reaction and ethene undergoes addition reaction.

Alykanes undergo substitution reaction and Alkenes and Alklyes undergo addition reaction which means Ethane undergo substitution and Ethene undergo addition reaction

Ethane undergoeshydrocarboncombustion, combining with oxygen to form carbon dioxide. The balanced chemical equation for the completecombustionofethaneis: This reaction is a source of primary energy.

Ethane undergo substitution reaction and ethene undergoes addition reaction.

Tree has lot of leaves which constantly shows transpiration . it is a loss of water through small tiny pores of leaves called stomata. when this water comes on the surface of leaf the water evaporates thereby causing cooling effect .therefore we feel pleasant sitting under a tree on a hot sunny day.

Na + Cl → NaClThe ionic compound NaCl is formed by the reaction between a metal, sodium, and a nonmetal, chlorine.

Heword Sufi is derivedfrom the Arabicword'suf' which means ' wool ' and which refers to the coarse woolen robes that were worn by the Prophet Muhammad (Choicest blessing and peace be upon him) and by his close companions. The goal of aSufiis none other than God Himself.

He word Sufi is derived from the Arabic word 'suf' which means ' wool ' and which refers to the coarse woolen robes that were worn by the Prophet Muhammad (Choicest blessing and peace be upon him) and by his close companions. The goal of a Sufi is none other than God Himself.

answer is b

b) option is correct

Explaination: Acid rainis caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogenoxides arereleased into the air.

thabks😀😁😂

Li will give its electron most easily.. so most powerful reducing agent

similarly F is the most oxidizing agent

1.OH-Hydroxyl2.COOH - Carboxylic Acid

-oh = alcohol -cooh = carboxylic acid

OH-alconal suffixCOOH-CARBOXYLIC ACID

1) alcohol2) carboxylic acid

Similarities between Lanthanides and Actinides

The elements of lanthanide and actinide series are characterized by filling of (n-2) f subshell. They possess almost similar outermost electronic configuration hence have similar properties. Following are the significant similarities:

Both have a prominent oxidation state of +3.They are involved in the filling of (n-2) f orbitals.They are highly electropositive and very reactive in nature.With an increase in atomic number, there is a decrease in atomic and ionic size.Both show magnetic properties.

Zn + FeSo4 = ZnSo4 + Fe

Here zinc being more reactive it can displace ferrous from ferrous sulphate solution and forms zinc sulphate solution

soap is alkaline in nature. testing it with a red litmus paper will change the colour of red litmus to blue. however, on testing it with blue Litmus it will not change the colour.So, the answer is Blue

why is soap alkaline ?

any soap is alkaline because it is made up of basic salts such as Sodium Hydroxide or potassium hydroxide. an alkaline solution induces saponification (conversion of fats or oils into soap by action of Alkaline substances).

Electrons = [ # of Electrons in carbon] {# of Carbon Atoms in 12g]Protons = [ # of Protons in carbon] {# of Carbon Atoms in 12g]Neutrons = [ # of Neutrons in carbon] {# of Carbon Atoms in 12g]

The number of atoms is actually one mole or Avogadro’s Number

Avogadro’s Number is 6.022141*10^23 atoms per mole. One mole of Carbon-12 isotope is is 12 g…

In Carbon-12 isotope there are 6 Electrons, 6 Protons, and 6 Neutrons.

Electrons = [6 Electrons] x [6.022141*10^23]Protons = [6 Protons] x [6.022141*10^23]Neutrons = [6 Neutrons] x [6.022141*10^23]

Linus Pauling and John Clarke Slater

No:12Element: MagnesiumValence:+2

The degree of pollution in our environment is rising by the day. It has increased rapidly with the advent of industrial revolution. The growing number of factories and vehicles on our planet has increased the pollution level many folds in the last few decades. While the smoke from the vehicles and factories has polluted the air adversely making it difficult to breathe, the industrial and residential waste has contributed majorly to the water and land pollution giving way to several serious illnesses.

Plastic: Major Cause of Environmental Pollution

Among other things, plastic plays a major role in pollution in today’s time. Plastic which is derived from fossil fuels such as oil and petroleum is being widely used for manufacturing numerous things including plastic bags, kitchenware, furniture, doors, sheeting, packing material, counter tops and what not. People prefer items made of plastic as these are light weight compared to wood or metal items and are also quite economical.

The increasing use of plastic is increasing the amount of plastic waste which is hard to dispose of. Plastic is a non-biodegradable substance. It breaks into pieces, deteriorates over the time but does not become one with the soil. It remains in the environment for hundreds of years and adds to environmental pollution. It goes into the landfills and leaks pollutants that damage soil and water. Plastic cannot even be disposed of by burning as on burning it produces poisonous gases that can cause serious diseases. Disposing plastic has thus become a big challenge today.

Plastic bags that form a major part of the plastic pollution are thus being banned in many countries. However, merely banning plastic bags shall not help. Ban must be imposed on other plastic items as well to bring down the environmental pollution.

Conclusion

It is high time we must understand the intensity at which plastic is destroying our environment and making life difficult for plants, animals, marine creatures as well as human beings. The use of plastic products must be lowered to ensure a cleaner environment.

A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bonds.

how many types?

4 Types of Chemical Bonds

1. Ionic bond

2. Covalent bond

3. Polar bond. ...

4. Hydrogen bond.

define ionic bond

Ionic bonding is a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions, and is the primary interaction occurring in ionic compounds. The ions are atoms that have gained one or more electrons and atoms that have lost one or more electrons.

define covalent bond

A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding.

Answer : Y > Z > X

More negative the standard potential,least the tendency of the cation to be reduced.The corresponding atom has larger tendency for oxidation and hence larger reducing power

Fibre is an important part of a healthy balanced diet. It can help prevent heart disease, diabetes, weight gain and some cancers, and can also improve digestive health. However, many people don't get enough fibre.

How many iron atoms are present in a stainless steel ball bearing having a radius of 0.254 cm ?The stainless steel contains 85.6% Fe by weight and has a density of 7.75g/cm cube.

this is an answer to similar ques.

given R° = k[A]²[B]

when [A] → 1.5[A] and [B] → 3[B]

then R° = k[1.5A]²[3B] = 2.25*3[A]²[B] = 6.75R°

so, option C

Answer: c)not changeExplanation:Surface tensionis caused by the effects of intermolecular forces at the interface.Surface tension depends onthe nature of the liquid, the surrounding environment and temperature. Liquids were molecules have large attractive intermolecular forces will have a largesurface tension.

Ionization, together withatomicand ionic radius, electronegativity, electron affinity, and metallicity, follows a trend on the periodic table of elements. Ionization energy generallyincreasesmoving from left torightacross an element period (row).

Electron affinityincreases upwardfor the groups and from left torightacross periods of a periodic table because the electrons added toenergylevels become closer to the nucleus, thus a stronger attraction between the nucleus and its electrons.

M1v1=m2v22×6=m2×6therefore m2=2M

Matter changes state whenenergyis added or taken away. Most matter changes because of heat energy. Changes inpressurecan change matter, too.

The atoms and molecules that make up matter are always moving. Even the molecules in solids are moving, just not very much.

When matter is heated enough, the molecules move faster and with greater energy. If enough heat is added, a solid can become liquid and a liquid can become gas.

In the same way, molecules slow down when they are cooled. Matter that is cooled to a certain point changes. For example, a liquid becomes a solid.