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Condensation polymers are any kind of polymers whose process of polymerization involves a condensation reaction.

AlCl3 → Al3+ + 3Cl- At cathode: Al3+ + 3e- → Al 3 mole of electrons corresponds 3 F charge So, required charge =3 F

The addition of bromine to most alkenes is so fast that when bromine is added dropwise to a solution of the alkene the red bromine color disappears almost immediately. In fact, this discharge of color is a useful qualitative test for alkenes.

An alkene reacts with conc. H2SO4 to yield an alkyl hydrogen tetraoxosulphate (VI). The compound formed undergoes hydrolysis when boiled with water to yield an alcohol.

The standard hydrogen electrode consists of hydrogen gas at 25oC

Data obtained from the question M = 60 g O = 24 g Empirical formula =? How to determine the empirical formula Divide by their molar mass M = 60\div120 = 0.5 O = 24 \div16 = 1.5 Divide by the smallest M = 0.5\div0.5 = 1 O = 1.5 \div0.5 = 3 Thus, the empirical formula of the oxide is MO₃

Oxygen is produced at the anode and hydrogen is produced at the cathode in dilute NaCl

Q =It t = 60 * 60=3600 I = 0.20 Q=0.20 * 3600 Q= 720C

HOCl is unstable and decomposes to release oxygen which oxidizes the dye to form a colourless compound.

- Recognise the functional group in the compound. This will determine the suffix of the name - Find the longest continuous carbon chain that contains the functional group (it won't always be a straight chain) and count the number of carbon atoms in this chain. This number will determine the prefix (the beginning) of the compound's name - Number the carbons in the longest carbon chain (Important: If the molecule is not an alkane (i.e. has a functional group) you need to start numbering so that the functional group is on the carbon with the lowest possible number). Start with the carbon at the end closest to the functional group. - Look for any branched groups: Name them by counting the number of carbon atoms in the branched group and referring to Table 4.6, these groups will all end in -yl. Note the position of the group on the main carbon chain. If there is more than one of the same type of branched group then both numbers must be listed (e.g. 2,4 -) and one of the prefixes listed in Table 4.7 must be used. Important: If the molecule is an alkane the branched group must be on the carbon with the lowest possible number. The branched groups must be listed before the name of the main chain in alphabetical order (ignoring di/tri/tetra). If there are no branched groups this step can be ignored. - For the alkyl halides the halogen atom is treated in much the same way as branched groups: To name them take the name of the halogen atom (e.g. iodine) and replace the -ine with -o (e.g. iodo) Give the halogen atom a number to show its position on the carbon chain. If there is more than one halogen atom the numbers should be listed and a prefix should be used (e.g. 3,4-diiodo- or 1,2,2-trichloro-). See Table 4.7 for a list of the prefixes. The halogen atoms must be listed before the name of the main chain in alphabetical order (ignore di/tri/tetra). If there are no halogen atoms this step can be ignored. - Combine the elements of the name into a single word in the following order: branched groups/halogen atoms in alphabetical order (ignoring prefixes) prefix of main chain name ending according to the functional group and its position on the longest carbon chain.

If the potassium manganate(VII) solution is acidified with dilute sulfuric acid, the purple solution becomes colourless. The salt that reacts with dilute hydrochloric acid to produce a pungent smelling gas which decolourizes acidified purple potassium tetraoxomanganate (VII) solution is Na\(_2\)SO\(_3\) Na\(_2\)SO\(_3\)(s) + HCl(aq) → NaCl(aq) + H\(_2\)O(l) + SO\(_2\)(g) When SO\(_2\) gas which is colourless with a pungent smell, reacts with acidified KMnO\(_4\), it becomes decolorized from purple colour.

Powdered marble reacts more rapidly with HCl than the chips of marble because: Surface area of powdered marble is more that of chips of marble and hence there is more collisions between the molecules of reactants Number of molecules increases. Energy of activation decreases Marble chips will not react with HCl

-The solubility of gases in liquids decreases with increasing temperature. Conversely, adding heat to the solution provides thermal energy that overcomes the attractive forces between the gas and the solvent molecules, thereby decreasing the solubility of the gas -The solubility of most solid or liquid solutes increases with increasing temperature

A salt that forms a white precipitate (ppt) with BaCl2 and is soluble in HCl is a sulphite (SO3\(^{2-}\)) salt. A salt that forms a white precipitate with BaCl₂ and is insoluble in HCl is a sulphate (SO₄²⁻), specifically a salt containing the sulfate anion, such as sodium sulfate (Na₂SO₄).

Activation energy must be achieved before reaction begin. This is because in any chemical reaction, chemical bonds in the reactants are broken, and new bonds in the products are formed