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What is the pH of a 2.62 x 10 <sup>-1</sup> M hypochlorous acid (HOCl) solution? NB the pKa for HOCl = 7.542. 1)13.42 2)7.54 3)4.06 4)10.48 5)0.58
4)10.48
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The half-life for a first-order reaction is 32s. What was the original concentration if, after 2.0 minutes, the reactant concentration is 0.062
Half life = 32 suse relation between rate constant and half life of 1st order reactionk = (ln 2) / k= 0.693/(half life)= 0.693/(32)= 2.166×10^-2 s-1we have:[A] = 0.062 Mt...
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What is the pH of an aqueous solution of 0.006534 M Ba(OH)<sub>2</sub> at 25<sup>o</sup>C? (Give your answer to two decimal places)
[OH−]=0.006534×2=0.0131M⇒pOH=−log(0.0131)=1.88As we know that,pH+pOH=14∴pH=14−pOH=14−1.88=12.12
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A weak acid has a pK value of 3.8. A solution contains 0.1 M of the acid and 0.3 M of the negatively charged ion. What is the pH of the solution? Express the result to two decimal places. pH =
3.8 – 0.1Мx – 0.3Mx=0.3*3.8/0.1=11.4
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Is citrus pectin (pKa 3.5) ionized at a pH lower than its pKa?
According to chemistry, A compound will be protonated if the pH is less than pKa and deprotonated if pH is more than pKa. Since here the pH is less than...
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How much 0.1200 M sodium hydroxide solution is need to titrate 13 mL of a 0.120 M sulfuric acid solution? Answer with 2 decimal places.
n(H2SO4) = C*V= 0.12*13n(NaOH) = 2n (H2SO4)= 2*0.12*13V(NaOH)=n/C=2*0.12*13/0.12=26.00 mLThe answer is 26.00 mL
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The half-life for a first-order reaction is 32 sec.What was the original concentration if,after 2.0 minuites, the concentration is 0.062 M ?
The half life is the time required for the concentration to drop to one-half its original value. 2 minutes is 2*60= 120 sec.If you have 120 sec and time of...
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Calculate the pOH of aqueous solution with the pH=11.0
express your answer using two decimal places
pOH=???
State whether the solution with the pH=11.0 is acidic, basic or neutral
Thanks!
pH + pOH = 14.0 Therefore: pOH = 14.0 – pH = 14.0 – 11.0 = 3.0 The solution with the pH = 11.0 is basic.
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A biochemist has 100 mL of a 0.10 M solution of a weak acid with pKa of 6.3. She adds 6.0 mL of 1.0 M HCL which changes the pH to 5.7. What was the pH of the original solution?
Find hydrogen ion concentration of the original solution using the law of mass conservation after some further algebraic manipulation: [H+]2+Ka[H+]-KaCa=0 (Ka - weak acid dissociation constant, Ca – weak acid...
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The molecular mass of NaCl is 58.4 g/mol. Calculate the amount of NaCl (in grams) needed to make 8 litres of a 6 molar solution. Give your answer to two decimal places.
m = n∙M= V∙c∙M = 8∙6∙58.4=2803.2 (g) Answer: 2803.2 g
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