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For a reaction to be feasible, \DeltaG has to be negative.

When two or more gases are mixed together at constant volume, there is an increase in entropy.

The rate of a reaction can be increased by adding a suitable catalyst. A catalyst is a substance which increases the rate of a chemical reaction but it is not used up (remains chemically unchanged at the end). It provides an alternative reaction pathway of lower activation energy.

When amount / volume of gaseous reactants equal amount / volume of gaseous products, the change in pressure has no effect on the equilibrium position.

In flame of pure hydrogen burning in air, the hydrogen (H2) reacts with oxygen (O2) to form water \(H_2O\) with the release of energy. Hydrocarbon combustion refers to the chemical reaction where a hydrocarbon reacts with oxygen to create carbon dioxide, water, and heat. The electrolysis of brine yields chlorine, hydrogen and sodium hydroxide.

The ozone layer in the stratosphere absorbs a portion of the radiation from the sun, preventing it from reaching the planet's surface. Most importantly, it absorbs the portion of UV light called UVB.

When an element exists in more than one crystalline form, those forms are called allotropes; the two most common allotropes of carbon are diamond and graphite. Graphite is used in pencils and lubricants. It is a good conductor of heat and electricity. Its high conductivity makes it useful in electronic products such as electrodes, batteries, and solar panels.

In the presence of heated platinum catalyst, ammonia reacts with excess air to produce nitrogen (II) oxide, NO, (instead of nitrogen) and water.

No expanded working has been attached for this question yet. The verified answer is Option C.

Reducing agent like SO\(_2\). Sulphur dioxide gas (SO\(_2\)) is bubbled through acidified potassium dichromate. The orange solution turns green.

When Hydrogen sulphide gas is bubbled through solutions of such metals, the colored sulphides are precipitated. Hydrogen sulphide is a also strong reducing agent.

The reactivity series of metals, also known as the activity series, refers to the arrangement of metals in the descending order of their reactivities. Na > Ca > Mg > Al > Zn > Fe > Sn > Pb > Cu > Ag. Considering metallic property which increases down the group, barium will be ranked calcium

Oxidation of Copper turnings with concentrated trioxonitrate (V) acid wil Cu + 4HNO\(_3\) → CuNO\(_3\) + 2H\(_2\)O +2NO\(_2\).

uses of wrought iron It is used to make decor items like table base, candle holder, curtain rods etc. It is used in making pipes. It is used in making fences and gates. It is used in making nuts, bolts, rivets etc. It is used in making chains.

Alkenes react in the cold with pure liquid bromine, or with a solution of bromine in an organic solvent like tetrachloromethane. The double bond breaks, and a bromine atom becomes attached to each carbon. The bromine loses its original red-brown colour to give a colourless liquid. Alkynes also react with bromine, decolorising it though not as immediate as alkenes.