At the half equivalence point [HA] = [A-] and pH = pKa
<span>if Ka is 5.2e-5 then pKa = pH = 4.28</span>
Answer : The labs were unable to reproduce the pharmaceutical company’s data.
Explanation : Any scientific claim must have reproducible experimental data. In this case, when the pharmaceutical company has the claim of reducing the cancer growth cells by 35% then by using the same manufacturing procedure for the drug and lab should be able to get this result. But they failed to match up with the results which clearly indicates that the labs were not able to produce the same results and hence they concluded that the pharmaceutical company's claims were invalid.
Answer:
8 electrons
Explanation:
Magnesium is present on group 2.
It has 2 valence electrons.
Electronic configuration of magnesium:
Mg₁₂ = 1s² 2s² 2p⁶ 3s²
1st energy level contain 2 electrons.(1s²)
2nd energy level contain 8 electrons. (2s² 2p⁶)
3rd energy level contain 2 electrons. (3s²)
3rs energy level of magnesium is called valence shell. It contain two valance electrons. Magnesium can easily donate its two valance electrons and get stable electronic configuration.
It react with halogens and form salt. For example,
Mg + Cl₂ → MgCl₂
The concentration of the Nitric acid solution : 0.114 M
<h3>Further explanation </h3>
Titration is a procedure for determining the concentration of a solution (analyte) by reacting with another solution whose known concentration (usually a standard solution) is called the titrant. Determination of the endpoint/equivalence point of the reaction can use indicators according to the appropriate pH range
Titrations can be acid-base titration, depositional titration, and redox titration. An acid-base titration is the principle of neutralization of acids and bases
Reaction
HNO₃ + NaOH → NaNO₃ + H₂O
Concentration a standard solution of sodium hydroxide : 0.0998 mol/dm³ , and the volume = 25 cm³
moles NaOH=

<em>From the equation, mol ratio HNO₃ : NaOH = 1 : 1, so mol HNO₃ = mol NaOH=</em><em>2.495 mlmoles</em>
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The volume of HNO₃ = 21.8 cm³, so the concentration :

They can all by seperrated or replicated.