Question Library

Water glass, also known as sodium silicate or alkali silicate glass, is a glassy solid made up of sodium oxide (Na\(_2\)O) and silica (silicon dioxide, SiO\(_2\)).

The order of reactivity of metals, from most to least reactive, is: Potassium: Most reactive and easily forms positive ions Sodium: Second most reactive Lithium: Third most reactive Calcium: Fourth most reactive Magnesium: Fifth most reactive Aluminum: Sixth most reactive Zinc: Seventh most reactive Iron: Eighth most reactive Tin: Ninth most reactive Lead: Tenth most reactive Hydrogen: Eleventh most reactive Copper: Twelfth most reactive Silver: Thirteenth most reactive Gold: fourteenth most reactive Platinum: Fifteenth most reactive

Nitrogen(I)oxide (nitric oxide) rekindles a brightly glowing splint just like oxygen does. This similarity is because both nitric oxide and oxygen support combustion.

The surface area of reactants affects the rate of a reaction between limestone and hydrochloric acid because it increases the number of collisions between the particles of the reactants. For example, if you have a large marble chip of calcium carbonate and hydrochloric acid, the acid can't reach all the calcium carbonate in the middle of the chip. If you break the marble chip into smaller pieces, you'll have a larger surface area for the acid to react with, and the reaction will happen faster.

Gay Lussac’s Law of Combining Volumes states that when gases react, they do so in volumes which bear a simple ratio to one another, and to the volume of the product(s) formed if gaseous, provided the temperature and pressure remain constant. C\(_2\)H\(_{4(g)}\) + 3O\(_{2(g)}\) → 2CO\(_{2(g)}\) + 2H\(_2\)O\(_{(g)}\) 1 mole : 3 moles Total volume required: 10 cm\(^3\) 50 cm\(^3\) Reacted Volume: 10 cm\(^3\) 30 cm\(^3\) Residual volume: 0 (50 - 30) = 20 cm\(^3\)

The hybridization scheme in ethyne is sp. In ethyne, each carbon atom's 2s orbital combines with one of its 2p orbitals to form two sp hybrid orbitals. The frontal lobes of these orbitals face away from each other, resulting in a straight line.

An organic compound with the general formula RCOR' is an alkanone, which is a type of ketone. Ketones: Have the general formula RCOR' and contain a carbonyl group, which is a carbon atom double-bonded to an oxygen atom.

Firstly, Al\(^{3+}\) + 3e\(^-\) → Al 1 mole of Al = 1F X 3e\(^-\) 1mole = 3F 4.5moles = X X = 4.5 X 3 = 13.5 F

The reaction between alkanoic acids and alkanols in the presence of an acid catalyst is called esterification: Esterification is a chemical reaction that combines an alcohol (ROH) and an organic acid (RCOOH) to form an ester (RCOOR) and water. The reaction can be catalyzed by an acid or a base.

C\(_x\)H\(_y\)O + 5O\(_2\) → 4CO\(_2\) + 4H\(_2\)O On balancing the equation, we should have X = 4 , y = 8 and O = 2 ⇒ C\(_4\)H\(_8\)O\(_2\) Since 2 is a common factor to the three atoms, we can divide through by 2, considering the fact that that formula is not in the option. We finally have C\(_2\)H\(_4\)O

Alkylation is the process of substituting an alkyl group into a benzene ring, replacing a hydrogen on the ring with a group like methyl or ethyl. Alkylation of benzene can be catalyzed by a number of substances, including: Aluminum chloride: A common catalyst for the Friedel-Crafts alkylation of benzene. Aluminum chloride acts as a Lewis acid, coordinating with halogens to generate an electrophile. Fluorinated alumina: Catalyzes the alkylation of benzene with propylene. Methyl- and ethylsilanes: Catalyze the alkylation of benzene with ethylene and propylene. Acidic zeolite catalysts: Such as mordenite, which can be used to alkylate benzene with 1-dodecene. Boron trifluoride: Catalyzes the alkylation of benzene with 2-propanol, forming a carbocation intermediate that attaches to the benzene ring

Benzene reacts with a mixture of concentrated nitric acid and concentrated sulphuric acid to form nitrobenzene at a temperature not exceeding 60^\circC. The reaction is known as the nitration of benzene.

The general molecular formula C\(_n\)H\(_{2n-2}\) represents that of an alkyne with its first member as ethyne

Covalent molecules have low melting and boiling points because of their weak intermolecular forces.The force of attraction between the molecules in a covalent compound is weak, so it takes little energy to break the bonds. Yes, all covalent compounds have a three-dimensional structure due to the directional nature of covalent bonds, which means the atoms within a molecule are arranged in a specific spatial orientation, giving the molecule a definite shape in three dimensions; this is explained by the Valence Shell Electron Pair Repulsion (VSEPR) theory.

When an alcohol is oxidized in a warm solution of potassium dichromate (VI) and dilute sulphuric acid, the solution changes colour from orange to green. This is because the Cr\(_2\)O\(_7\)\(^{2-}\) ions in the solution are reduced to Cr\(^{3+}\) ions. This colour change can be used to identify alcohols. Only alcohols will cause the solution to change colour from orange to green.