(b) The reaction between an acid and a base produces salt and water. A mixture of
100.0 cm' of 0.431 mol dm HCI solution and 100.0 cm' of 0.216 mol dm Ba(OH)2, solution is
added into a constant-pressure calorimeter. Determine the final temperature of the mixture if the
initial temperature of both solutions is 20.5 °C.
[5]
[Specific heat capacity of water is 4.18 Jg'°C and heat of neutralisation is -56.2 kJ mol-')

Explanation:

The neutralization reaction equation

2 HCl + Ba(OH)2 → Bacl₂ + 2 H₂O

number of mole of HCl = 0.431 × ( 100 / 1000) dm³ = 0.0431 mol

number of mole of Ba(OH)2 = 0.216 × ( 100 / 1000) dm³ = 0.0216 mole

comparing their stoichometry mole ratio

2 HCl react with 1 mole of Ba(OH)₂ TO yield 2 mole of water

0.0431 will react with 0.0216 mole to yield 0.0431 mole of water

H⁺ + OH⁻ → H₂O

q ( quantity of heat ) = heat of neutralization × number of mole of water = -   0.0431× -56.2 kJmol⁻¹= -2.42784 KJ

q = mc ( T₂ - T₁)

q / mc = T₂ - T₁

T₂ = (q / mc) + T₁ = ( 2427.84 J / ( 200 g × 4.184) + 20.5 °C = 23.401°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.  

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante