Answer:
Light demonstrates wave-like and particle-like characteristics
Explanation:
Light itself is a wave but under circumstance it will present particle-like charcteristics. This is called wave-particle duality :)
The average atomic mass of the element = 35.5
calculation
average atomic mass = sum of the masses of its isotope each multiplied by its natural abundance.
that is
[(75 x35) +(25 x37)] /100 = 35.5
I think 25 grams.
Z = 76^2.2 x pi
Mass is both a property of a physical body and a measure of its resistance to acceleration when a net force is applied. An object's mass also determines the strength of its gravitational attraction to other bodies. The basic SI unit of mass is the kilogram.
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.
Answer:
0.5077 moles
Explanation:
Data Given:
Moles = n = <u>???</u>
Temperature = T = 300 K
Pressure = P = 380 mmHg = 0.50 atm
Volume = V = 25 L
Formula Used:
Let's assume that the hydrogen gas in balloon is acting as an Ideal gas, the according to Ideal Gas Equation,
P V = n R T
where; R = Universal Gas Constant = 0.082057 atm.L.mol⁻¹.K⁻¹
Solving Equation for n,
n = P V / RT
Putting Values,
n = (0.50 atm × 25 L) / (0.082057 atm.L.mol⁻¹.K⁻¹ × 300 K)
n = 0.5077 moles