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What are Chemical properties?

A chemical property is any of a material's properties that becomes evident during a chemical reaction.

Chemical property is any quality that can be established only by changing a substance's chemical identity.

Chemical properties cannot be determined just by viewing or touching the substance; the substance's internal structure must be affected for its chemical properties to be investigated.

 

E.g. heat of combustion, reactivity with water, pH, and electromotive force.

 

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What are Physical properties?

A physical property is any property that is measurable, whose value describes a state of a physical system.

The changes in the physical properties of a system can be used to describe its transformations between its momentary states.

Physical properties are often referred to as observables.

E.g. color, smell, freezing point, boiling point, melting point, infra-red spectrum, attraction (paramagnetic) or repulsion (diamagnetic) to magnets, opacity, viscosity and density.

 

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What is an Ion?

An ion is an atom or molecule, in which the total number of electrons is not equal to the total number of protons, giving the atom or molecule a net positive or negative electrical charge.

Ions can be created, by either chemical or physical means, via ionization.

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What is a cation and anion?

If a neutral atom loses one or more electrons, it has a net positive charge and is known as a cation.

If an atom gains electrons, it has a net negative charge and is known as an anion.

An ion consisting of a single atom is an atomic or monatomic ion; if it consists of two or more atoms, it is a molecular or polyatomic ion.

Because of their electric charges, cations and anions attract each other and readily form ionic compounds, such as salts.

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What are chemical salts?

Salts are ionic compounds that result from the neutralization reaction of an acid and a base.

They are composed of related numbers of cations (positively charged ions) and anions (negative ions) so that the product is electrically neutral (without a net charge).

There are several varieties of salts. Salts that hydrolyze to produce hydroxide ions when dissolved in water are basic salts, whilst those that hydrolyze to produce hydronium ions in water are acidic salts. Neutral salts are those that are neither acid nor basic salts.

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What is an Acid?

An acid is a chemical substance, whose aqueous solutions are characterized by a sour taste, the ability to turn blue litmus red, and the ability to react with bases and certain metals (like calcium) to form salts.

Aqueous solutions of acids have a pH of less than 7.

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What is a Base?

Bases are substances that, in aqueous solution, are slippery to the touch, tastes bitter, changes the color of indicators (e.g., turns red litmus paper blue), reacts with acids to form salts, and promotes certain chemical reactions.

Examples of bases are the hydroxides of the alkali and alkaline earth metals like NaOH, Ca(OH)2, etc.

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What is an atom?

An atom is the smallest unit of matter that defines the chemical elements.

Every solid, liquid, gas, and plasma is made up of neutral or ionized atoms.

Atoms are very small: the size of atoms is measured in picometers – trillionths (10−12) of a meter.

Every atom is composed of a nucleus and one or more electrons that orbit the nucleus.

The nucleus is made of one or more protons and typically a similar number of neutrons.

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What is a Chute?

A chute is a vertical or inclined plane channel, or passage through which objects are moved by means of gravity.

Chutes may be round, square or rectangular at the top and/or the bottom.

E.g. a Coal chute at the end of conveyor head pulley, in Coal transfer towers/ points.

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What is retrofitting of steam turbines?

Retrofitting is the addition of new technology or features, to older systems.

Retrofitting of steam turbines refers to, the replacing of steam turbine section with a new bladed rotor and carrying out repairs in the stator to improve the turbine's performance.

Retrofitting is cheaper than replacing the entire turbine.