Answer:
it is the example of molecules
Answer:
18.94%.
Explanation:
- The decay of carbon-14 is a first order reaction.
- The rate constant of the reaction (k) in a first order reaction = ln (2)/half-life = 0.693/(5730 year) = 1.21 x 10⁻⁴ year⁻¹.
- The integration law of a first order reaction is:
<em>kt = ln [A₀]/[A]</em>
k is the rate constant = 1.21 x 10⁻⁴ year⁻¹.
t is the time = 13,750 years.
[A₀] is the initial percentage of carbon-14 = 100.0 %.
[A] is the remaining percentage of carbon-14 = ??? %.
∵ kt = ln [Ao]/[A]
∴ (1.21 x 10⁻⁴ year⁻¹)(13,750 years) = ln (100.0%)/[A]
1.664 = ln (100.0%)/[A]
Taking exponential for both sides:
5.279 = (100.0%)/[A]
<em>∴ [A]</em> = (100.0%)/5.279 = <em>18.94%.</em>
The equation is already balanced
2AgNO3 + MgCl2 => 2AgCl + Mg(NO3)2
Answer:
I say for her to test her suspicion by going to see an allergist to diagnose the allergy.
The serving of peanut butter contains 117kcal
<h3>Calculation of calories of food Nutrients</h3>
1 gram of both carbohydrate and protein contains 4 (kcal)
1 gram of fat contains 9 (kcal)
But peanut butter contains 5g of fat. The kilocalories of fat present is;
1 g = 9 kcal
5g = F
F = 5×9
F = 45 kcal
The kilocalories of carbohydrates present is;
1g = 4kcal
12g = C
C= 12×4
C = 48kcal
The kilocalories of proteins present is;
1g = 4kcal
6 g = P
P = 4× 6
P = 24 kcal
Therefore, the total kilocalories of the peanut = 45 + 48 + 24 = 117kcal
Learn more about kilocalories here:
brainly.com/question/6423812