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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.

N\(_{2(g)}\) + 3H\(_{2(g)}\) ⇔ 2NH\(_{3(g)}\) In the Haber process, the forward reaction is exothermic and the backward reaction is endothermic. If the temperature is decreased, the yield from the exothermic direction is increased i.e. the forward reaction is increased.

The definition of enthalpy change is \DeltaH = \DeltaU + Pex(\DeltaV) The enthalpy change is zero because both terms on the right are zero in free expansion of an ideal gas. There is no external pressure in a free expansion, so P (ex) = 0. And the internal energy change, \DeltaU of free expansion in a closed system is zero since no inter molecular forces have to be overcome. The temperature remains constant and no heat is absorbed or released.

Alkanones also known as ketones have the general formula R\(_2\)CO

Bacteria of the genus Propionibacterium produce propionic acid (Propanoic Acid) as the end-product of their anaerobic metabolism. This class of bacteria is commonly found in the stomach of ruminants and the sweat glands of humans, and their activity is partially responsible for the odour of both Swiss cheese and sweat.

In electro-valency the oxidation number of the participating metal increases.

In a neutral atom, the atomic and ionic radius is the same, but many elements exist as anions or cations. If the atom loses its outermost electron (positively charged or cation), the ionic radius is smaller than the atomic radius because the atom loses an electron energy shell. Yes ionic radius is only less than atomic radius for a metal.