Answer:
I am sure that the C one is correct
The single most important chemical weathering agent is Carbon dioxide.
Weathering refers to the process that change the physical and chemical character of rock at or near the surface. Weathering has a dramatic impact on the composition of Earth's atmosphere. Chemical weathering removes carbon dioxide from the atmosphere, allowing it to be transformed into limestone and stored in the crust. Without chemical weathering, the elevated levels of carbon dioxide in the atmosphere would have long made Earth too hot to sustain life.
Answer:
Ununennium.
Explanation:
Ununennium, also known as <em>eka-francium</em> or <em>element 119</em>, is the hypothetical chemical element with symbol <em>Uue</em> <em>and atomic number 119. </em> It's Mass number is [315] (predicted), as we as it is existing on the periodic table hence its symbol: <em>Uue</em>
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:
Decreases
Explanation:
The atmospheric pressure on the surface of the mercury pushes it up the evacuated tube until the downward pressure of the mercury equals the atmospheric pressure.
If the atmospheric pressure decreases, the mercury doesn't have to rise as high.
The mercury height decreases.