The correct structure has the hydroxyl group on the second carbon with two methyl groups on the same carbon.

2-butyne has the structure CH3-CH≡C-CH3, with the triple bond between the second and third carbon.

2-methylpropane has a branched structure with a methyl group on the second carbon.

The mole is the SI unit for measuring the amount of substance.

Molality is defined as moles of solute per kilogram of solvent, hence the unit is mol/kg.

Molarity is defined as moles of solute per liter of solution, hence the unit is mol/L.

Aldehydes contain the functional group -CHO, which is characterized by a carbonyl group (C=O) bonded to a hydrogen atom.

Carboxylic acids contain the -COOH functional group.

Alcohols contain the hydroxyl group (-OH) as their functional group.

The general formula for alkenes is C_nH_(2n), where n is the number of carbon atoms.

The general formula for alkynes is C_nH_(2n-2), where n is the number of carbon atoms.

Cesium (Cs) is the heaviest alkali metal.

Butane has the molecular formula C4H10.

Fluorine is the most electronegative element in the p-block.

Methane (CH4) is the simplest alkane, consisting of one carbon atom.

Acetylene (C2H2) is the simplest alkyne.

Acetone (propan-2-one) is the simplest ketone, with the formula (CH3)2CO.

Formic acid (HCOOH) is stronger than acetic acid (CH3COOH) due to the presence of a hydrogen atom directly attached to the carbonyl carbon, which stabilizes the conjugate base.

A buffer solution resists changes in pH upon the addition of small amounts of acid or base.

A saturated solution contains the maximum amount of solute that can dissolve at a given temperature.

In an exothermic reaction, the enthalpy change (ΔH) is negative because heat is released.

Entropy is a measure of disorder in a system, and it tends to increase in spontaneous processes.

The Freundlich adsorption isotherm is applicable to heterogeneous surfaces and describes multilayer adsorption.

For a spontaneous process, the Gibbs free energy change (ΔG) is less than 0 (ΔG < 0).

A negative Gibbs free energy change (ΔG < 0) indicates that the process is spontaneous.

Heat capacity depends on the amount of substance; it is not a constant value.

In an endothermic reaction, heat is absorbed, resulting in a positive ΔH.

Neodymium is used in making strong permanent magnets due to its magnetic properties.

CN- is a strong field ligand and causes a large splitting of d-orbitals, leading to low-spin complexes.

Water has a higher boiling point due to strong hydrogen bonding.