oops pls forgive me I accidentally did the wrong question.
Answer:
8.96 g/mL
Explanation:
density = mass / volume
density = 134.3g / 15.0 mL
density = 8.96 g/mL
Answer:
The cycling of matter is important to many Earth processes and to the survival of organisms the existing matter must cycle continuously for this planet to support life Water, carbon, nitrogen, phosphorus, and even rocks move through cycles If these materials did not cycle, Earth could not support life.
Explanation:
Letter C on the model titration curve corresponds to the point where pH equals the numerical value of pKa for HPr
<h3>What is a titration curve?</h3>
A titration curve is a graph of the pH of a solution against increasing volumes of an acid or a base that is added to the solution.
The pH of a solution is the negative logarithm to base ten of the hydrogen ion concentration and is a measure of the acidity or alkalinity of the solution.
The pKa is the acid dissociation constant of an acid solution.
In a titration of a strong acid and strong base, the pH at equivalence point is equal to the pKa of the acid.
The equivalence point is the point when equal moles of acids and base has reacted.
In the given titration curve, pH = pKa at point C.
In conclusion, for a titration curve of strong acid and base, at equivalence point, pH is equal to pKa of acid.
Learn more about equivalence point at: brainly.com/question/23502649
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Answer:
67.6 years is the time the isotope take to decay from 0.900g to 0.170g
Explanation:
The radioactive decay follows first order law:
Ln [A] = -kt + ln[A]₀
<em>Where [A] is concentration after time t,</em>
<em>k is decay constant:</em>
<em>k = ln 2 / t(1/2)</em>
<em>k = ln2 / 28.1 years</em>
<em>k = 0.02467 years⁻¹</em>
<em>[A]₀ = Initial concentration.</em>
<em />
We can replace concentration and use the mass of the isotope:
Ln [A] = -kt + ln[A]₀
Ln [0.170g] = -0.02467 years⁻¹t + ln[0.900g]
-1.667 = -0.02467 years⁻¹t
t =
<h3>67.6 years is the time the isotope take to decay from 0.900g to 0.170g</h3>