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When we ignite a candle, the hydrocarbon reacts with oxygen (in excess) to produce carbon dioxide and water. The burning sets an air current which gives dome shape to candle flame and it helps to get complete combustion at the bottom and the outer surface of the flame. CO\(_2\) is produced

Collision theory is the theory used to predict the rates of chemical reactions, particularly for gases. The collision theory is based on the assumption that for a reaction to occur it is necessary for the reacting species (atoms or molecules) to come together or collide with one another.

Ammonia gas can be removed from a dessicator by adding a conc. H2SO4 so as to neutralize it since ammonia gas is basic.

Aluminium doesn’t react with either dilute or concentrated trioxonitrate (V) acid because an insoluble oxide is formed on its surface which renders it passive. It will depend on the concentration of the nitric acid used…. Although aluminium reacts with dilute nitric acid to produce aluminium nitrate and hydrogen gas, concentrated (>60%) nitric acid is such a powerful oxidising agent that it instantly causes a thin layer of aluminium oxide to coat the surface of the aluminium

During the electrolysis of brine, the chlorine ions are discharged at the anode and are oxidized. While at the cathode Hydrogen ion is discharged.

Half-life, in radioactivity, the interval of time required for one-half of the atomic nuclei of a radioactive sample to decay (change spontaneously into other nuclear species by emitting particles and energy), or, equivalently, the time interval required for the number of disintegrations per second of a radioactive material to decrease by one-half

The law of multiple proportion states that when element A and B combine to form more than one chemical compound then the various masses of sample A react with a fixed mass of sample B are in a simple multiple ratio.

PH+POH=14 p\(^{H}\) = Log [H\(^+\)] p[H\(^+\) ] = 2.0 X 10\(^{-11}\)moldm\(^{-3}\) p\(^{H}\) = Log [2.0 X 10\(^{-11}\)] p\(^{H}\) = 10.70 10.70+ p\(^{OH}\) =14 p\(^{OH}\) = 14 -10.70 = 3.30

This is typical of what happens with any equilibrium where the forward reaction is exothermic. Increasing the temperature decreases the value of the equilibrium constant. Where the forward reaction is endothermic, increasing the temperature increases the value of the equilibrium constant. Endothermic reaction has a Positive Enthalpy change. Exothermic reaction has a negative enthalpy change.

The conductivity of a solution depends on the number of charge carriers (the concentrations of the ions), the mobility of the charge carriers and their charge. Theoretically, conductivity should increase in direct proportion to concentration.

Metals above hydrogen in the activity series can displace or replace hydrogen present in water (H\(_2\)O) example of such metals are Ca, K, Na etc. But the metals below hydrogen in the activity series cannot replace hydrogen in the activity series example of such metals are Cu, Hg.

P 6 = 2, 4 Q 11 = 2, 8, 1 R 15 = 2, 8, 5 S 17 = 2, 8, 7 Given the above is the electronic arrangement of PQRS elements, Q will form an electrovalent bond with S. Without argument, D is the answer because electrovalency involves the transfer of electron. Already, Q is 11 with electronic configuration of 2, 8, 1, i.e. having 1 valence electron which is ready to be lost by the atom of element Q, also, S is 17, with electronic configuration of 2, 8, 7. There the 7 valence electron of S attracts that only 1 electron to attain a stable octet structure.

During the electrolysis of copper using platinum electrode, Cu and H migrate to the cathode while,SO\(_4\) and OH migrate to the anode.CU is then discharged preferentially at the cathode, acquiring two electrons and is deposited as metallic copper, while OH is discharged preferentially at the anode and deposited as gaseous oxygen, then the SO\(_4\) and H still in the solution react, thereby making d solution acidic and then changing the litmus paper red which is the test for acids.

Yes, Toluene is used in making explosives, based on information from the textbook "New School Chemistry", pg 541. Phenol is used as a starting material to makes explosive materials such as picric acid. Picric acid is one of the most acidic phenol. Like other strongly nitrated organic compounds, picric acid is an explosive. Toluene, however, is used to produce a stronger explosive material called TriNitroToluene (TNT). Therefore Toluene is the most appropriate answer for this question but in situations where you don't find Toluene in the options provided, then Phenol makes a viable answer.

Sieving is a simple and convenient technique of separating particles of different sizes.