The enthalpy of solution of sodium hydroxide is –44.4 kj/mol. when a 13.9-g sample of naoh dissolves in 250.0 g of water 23.0 °c in a coffee-cup calorimeter, what is the final temperature of the solution assuming no heat is lost to the surroundings. the solution has the same specific heat of 4.184 j/g-k.

The final temperature of the NaOH solution: T₂ = 37 °C  

Explanation:

Given: The enthalpy of NaOH solution: =  – 44.4 kJ/mol,

The specific heat capacity of solution: c = 4.184 J/g.K

Given mass of solute (NaOH): w = 13.9 g, Molar mass of NaOH: m = 40 g/mol

Mass of the solvent: W = 250 g

Initial temperature of the solution: T₁ = 23 °C = 23 + 273 = 296 K    (∵ 0°C = 273 K)

Final temperature of the solution: T₂ = ?

The number of moles of NaOH =

So the amount of heat released (ΔH) by dissolution of 13.9 g NaOH:

(∵ 1 kJ = 1000J )

Since the specific heat capacity is given by the equation:

Here,  M is the total mass of the solution = w + W = 13.9 g + 250 g =263.9 g

Thus the increase in the temperature (ΔT) can be calculated as:

(∵ 0°C = 273 K)

Therefore, the final temperature of the NaOH solution: T₂ = 37 °C  

answer: option (b) is the correct answer.

explanation:

a covalent bond is formed by sharing of electrons. whereas polarity arises due to difference in electronegativity of two atoms.

therefore, more is the electronegativity of an atom which combines with the titanium, more readily it will induce a partial positive and negative charge.

thus, out of the given options fluorine is most electronegative and has an incomplete octet. therefore, it will readily combine with titanium to share the electrons and complete its octet.