Alkynes are hydrocarbons with at least one triple covalent bond.
Answer is: 25,06 kJ of energy must be added to a 75 g block of ice.
ΔHfusion(H₂O) = 6,01 kJ/mol.
T(H₂O) = 0°C.
m(H₂O) = 75 g.
n(H₂O) = m(H₂O) ÷ M(H₂O).
n(H₂O) = 75 g ÷ 18 g/mol.
n(H₂O) = 4,17 mol.
Q = ΔHfusion(H₂O) · n(H₂O)
Q = 6,01 kJ/mol · 4,17 mol
Q = 25,06 kJ.
For this reaction to proceed, the following bond breaking should occur:
*one C-H bond
* one Cl-Cl bond
After, the following bond formations should occur:
*one C-Cl bond
*one H-Cl bond
Now, add the bond energies for the respective bond energies which can be found in the attached picture. For bond formations, energy is negative. For bond breaking, energy is positive.
ΔHrxn = (1)(413) + (1)(242) + 1(-328) + 1(-431) =
<em>-104 kJ</em>
What do you mean by this question?
Answer:
Option B, aspirin’s ester group provides greater digestibility to aspirin
Explanation:
Aspirin ester group has three parts
- carboxylic acid functional group (R-COOH)
- ester functional group (R-O-CO-R')
- aromatic group (benzene ring)
Aspirin is a weak acid and hence it cannot dissolve in water readily. The reaction of Aspirin ester group with water is as follows -
aspirin
(acetylsalicylic acid) + water → salicylic acid + acetic acid
(ethanoic acid)
Aspirin passes through the stomach and remains unchanged until it reaches the intestine where it hydrolyses ester to form the active compound.