Answer:
0.06mole
Explanation:
Given parameters:
Volume of balloon = 2.5L
T = 343.5K
P = 66.7kPa; in atm gives = 0.66atm
Unknown:
Number of moles of He = ?
Solution:
To solve this problem, we use the ideal gas equation.
It is mathematically expressed as;
Pv = nRT
where p is the pressure
v is the volume
n is the number of moles
R is the gas constant
T is the temperature
0.66 x 2.5 = n x 0.082 x 343.5
n = 0.06mole
Answer:
The correct order of increasing reactivity toward nucleophilic acyl substitution is E < D < C < A < F < B.
Explanation:
The stability of the leaving group best determines the manner of reactivity of carboxylates to nucleophilic substitution after the substitution of the nucleophile to the leaving group. The leaving group should, therefore, be protonated with hydrogen ion in the solution to form a stable molecule. From the given list: The leaving group for A, Ethyl thioacetate will be ethanethiol. For B, Acetyl chloride will be Hydrochloric acid. For C, Sodium acetate will be Sodium Hydroxide. For D, Ethyl acetate will be Ethanol. For E, Acetamide will be Ammonia, and for F, Acetic anhydride will be Ethanoic acid. The reactivity of the substitution reaction is dependent on the stability of these leaving groups. The stability of these leaving groups depends on their pKa, and the more the pKa, the lesser the acidity of the leaving group, and the lower the reactivity. Therefore, considering their pKa: A is 8.5, B is -7, C is 13.8, D is 15.9, E is 36, and F is 4.8. When we rearrange this pKa in descending order, we have E, D. C, A, F, B. Which is also the increased reactivity of the nucleophilic acyl substitution.
0.01742919 is the answer because i worked it out
