it is called the Earth's rotation
<u>Answer:</u> The percentage abundance of and isotopes are 77.5% and 22.5% respectively.
<u>Explanation:</u>
Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.
Formula used to calculate average atomic mass follows:
.....(1)
Let the fractional abundance of isotope be 'x'. So, fractional abundance of isotope will be '1 - x'
- <u>For isotope:</u>
Mass of isotope = 35 amu
Fractional abundance of isotope = x
- <u>For isotope:</u>
Mass of isotope = 37 amu
Fractional abundance of isotope = 1 - x
Average atomic mass of chlorine = 35.45 amu
Putting values in equation 1, we get:
Percentage abundance of isotope =
Percentage abundance of isotope =
Hence, the percentage abundance of and isotopes are 77.5% and 22.5% respectively.
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.
Explanation:
Jen runs at a little under 10m per second. Ann runs about 6m per second. Jen won because her time was faster. She reached 50m by 6 seconds while it took Ann 8 seconds. If the graph displayed their motion stopping, the line would continue straight horizontally along the 50m line as they would not be running anymore.
Answer: It is important for an equation to be balanced because if it is not then the reactants won't match the products.
Explanation: I don't know if you will understand this but here:
Let's say you're cooking eggs, you're reactants so to speak would be 3 eggs and 1 tablespoon of oil so you put it together using heat and a pan. Your products have to match what you have in the beginning. You cannot have an equation that looks like this
Reactants = 3eggs + 1Tbsp oil ---pan/heat---> 6eggs + 1 cup of oil
You cannot get something from what you don't have. The number of how much of an element you have must be the same of both sides of the equation.