<span>The best choice is hypochlorous acid nitrous acid (HNO2) because it has the nearest value of pK to the desired pH.
pKa of </span>nitrous acid<span> is 3.34
If we know pKa and pH values, we can calculate the required ratio of conjugate base (NO2⁻) to acid (HNO2) from the following equation:
pH=pKa + log(conc. of base)/( conc. of acid)
</span><span>3.19=3.34 + log c(NO2⁻)/c(HNO2)
</span><span>3.19 - 3.34 = log c(NO2⁻)/c(HNO2)
-0.15 = log c(NO2⁻)/c(HNO2)
c(NO2⁻)/c(HNO2) = 10⁰¹⁵ = 1.41
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Answer:
Explanation:
When calculating an empirical formula from percentages, assume you have a 100g sample. This allows you to convert the percentages directly to grams, because X % of 100g is X grams.
So:
24.42 % = 24.42 g Ca, 17.07% = 17.07g N, 58.5% = 58.5g O
The next step is to divide each mass by their molar mass to convert your grams to moles.
24.42/40.08 = 0.6092 mol
17.07/14.01 = 1.218 mol
58.85/15.99 = 3.680 mol
Then you will divide all of your mol values by the SMALLEST number of moles. This gives you whole numbers that are the mole ratio (subcripts) of the empircal formula.
0.6092 mol/0.6092 mol = 1
1.218 mol/0.6092 mol = 2
3.680 mol/0.6092 mol = 6
So the empirical formula is
Light energy is turned into chemical energy when <span>when a photochemically excited special chlorophyll molecule of the photosynthetic reaction center loses an electron, undergoing an oxidation reaction.
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Answer:
Hence, 15.99 g of solid Aluminum Sulfate should be added in 250 mL of Volumetric flask.
Explanation:
To make 0.187 M of Aluminum Sulfate solution in a 250 mL (0.250 L) Volumetric flask
The molar mass of Aluminum Sulfate = 342.15 g/mol
Using the molarity formula:-
Molarity = Number of moles/Volume of solution in a liter
Number of moles = Given weight/ molar mass
Molarity = (Given weight/ molar mass)/Volume of solution in liter
0.187 M = (Given weight/342.15 g/mol)/0.250 L
Given weight = 15.99 g
