When a 2.5 mol of sugar (c12h22o11) are added to a certain amount of water the boiling point is raised by 1 celsius degree. if 2.5 mol of aluminum nitrate is added to the same amount of water, by how much will the boiling point be changed? use 3 – 4 sentences to explain your answer. ! will give most

The boiling point of the water by adding 2.5 moles of aluminium nitrate will be changed by 4°Celsius.

When sugar is dissolved in x kg of water:

ΔT₁ = 1°C = 274 K (0°C = 273 K)

Number of moles of sugar dissolved = 2.5 mol

i = Van't Hoff factor of sugar = 1

ΔT₁ = iKf × molality = iKf × moles of sugar/weight of solvent in kg

ΔT₁ = 274 K = 1 × Kf × 2.5 mol / xkg (1)

When aluminium nitrate is dissolved in x kg of water:

Number of moles of aluminium nitrate dissolved = 2.5 mol

Al(NO₃)₃ (aq) = Al₃+ (aq) + 3NO₃⁻ (aq)

i = Van't Hoff factor of aluminium nitrate is 4

Aluminium nitrate being ionic compound will get dissociated into its constituting ions. The value of i of the ionic compound is equivalent to the number of discrete ions in a formula unit of a substance.

ΔT₂ = iKf × moles of Al (NO₃)₃ / weight of solvents in Kg

ΔT₂ = 4 × Kf × 2.5 mol / x Kg (2)

On dividing 1 and 2 we get,

delta T₂ = 4 × 274 K = 4 × 1°C = 4°C

The boiling point of the water by adding 2.5 moles of aluminium nitrate will be changed by 4°C.

c.

explanation:

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.