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Fractional distillation is used to separate mixtures into its component parts or fractions with the difference in boiling points between successive fractions must be more than 10^\circC. An example is the liquid nitrogen and oxygen are then separated by fractional distillation .

Using the combined gas law formula, In this problem, the oxygen is contained in a 2.76 L container at a temperature of 300 K. Since the gas remains in the same container and the temperature is not stated to change, both the volume( V) and the temperature (T) are constant. The Ideal Gas Law is defined as: PV = nRT Since the quantity of gas is reduced by one-half ( n\(_2\) = \(\frac{1}{2}\) n\(_1\)), the pressure must also be reduced by one-half. P\(_2\) = \(\frac{1}{2}\) P\(_1\) P\(_2\) = \(\frac{0.825}{2}\) = 0. 4125 atm Rounding to three decimal places (as provided in the options), the pressure is 0.413 atm.

They are the most stable due to having the maximum number of valence electrons their outer shell can hold. Therefore, they rarely react with other elements since they are already stable.

NH\(_4\)NO\(_3\) Ammonium Trioxonitrate(V) , unlike all other metallic trioxonitrates(v), decomposes on heating to give nitrogen(i)oxide N\(_2\)O and water.

The element is Phosphorus in group 5 with valencies of 3 and 5. The electronic configuration of phosphorus is 2,8,5. Hence it has two valencies of +5 and -3. Since we do not have 5 in the options provided, the valency is 3.

Duralumin is an alloy made up of 90% aluminum, 4% copper, 0.51% magnesium, and less than 1% manganese.

Polysaccharides are long chains of monosaccharides linked by glycosidic bonds. Three important polysaccharides, starch, glycogen, and cellulose, are composed of glucose.

Molar mass of methane = 16g/mol At S.T.P. its 8g occupies 11.2 so 16g occupies 22.4 dm\(^3\) Molar mass of propane = 44g/mol\(^-1\) occupies 22.4dm\(^3\) at S.T.P so 22g will occupy 11.2dm\(^3\)

Sulfuric acid is flushed with a mild, soapy solution if the burns are not severe. Sulfuric acid feels hot when water is added to the acid, but it is better to flush the area and not leave the acid on the skin. Don't try to neutralize the burn with acid or alkali. This could cause a chemical reaction that worsens the burn.

Charles' law describes the effect of temperature changes on the volume of a given mass of gas at a constant pressure.

The element with atomic number 17 is Chlorine with a valency of -1, that is it needs to receive an electron or possibly lose seven electrons to obey the octet rule.

Destructive distillation of a tonne of coal can produce 700 kg of coke, 100 liters of liquor ammonia, 50 liters of coal tar and 400 M\(^3\) of coal gas

A lye is a metal hydroxide traditionally obtained by leaching wood ashes, or a strong alkali which is highly soluble in water producing caustic basic solutions / an alkaline solution that is used to make soaps. "Lye" most commonly refers to sodium hydroxide (NaOH), but historically has been used for potassium hydroxide (KOH).

The reaction of calcium carbide with water, producing acetylene and calcium hydroxide, was discovered by Friedrich Wöhler in 1862. This reaction was the basis of the industrial manufacture of acetylene, and is the major industrial use of calcium carbide.

A Mixture contains two or more constituents which can be easily separated by physical methods. Examples include Air, Soil, Palm oil, Sea water, Blood, Crude oil, etc