2. What is the change in the atomic number when an atom emits an alpha particle? (1 point)
1 answer:
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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:
(a) -0.00017 M/s;
(b) 0.00034 M/s
Explanation:
(a) Rate of a reaction is defined as change in molarity in a unit time, that is:
Given the following reaction:
We may write the rate expression in terms of reactants firstly. Since reactants are decreasing in molarity, we're adding a negative sign. Similarly, if we wish to look at the overall reaction rate, we need to divide by stoichiometric coefficients:
Reaction rate is also equal to the rate of formation of products divided by their coefficients:
Let's find the rate of disappearance of the reactant firstly. This would be found dividing the change in molarity by the change in time:
(b) Using the relationship derived previously, we know that:
Rate of appearance of nitrogen dioxide is given by:
Which is obtained from the equation:
If we multiply both sides by 4, that is:
This yields:
[tex]r_{NO_2} = \frac{\Delta [NO_2]}{\Delta t} = -2\frac{\Delta [N_2O_5]}{ \Delta t} = -2\cdot (-0.00017 M/s) = 0.00034 M/s[tex]