Decide whether each of the molecules in the table below is stable, in the exact form in which it is drawn, at pH=2. If you decide at least one molecule is not stable, then redraw one of the unstable molecules in its stable form below the table. (If more than one molecule is unstable, you can pick any of them to redraw.) HO × 5 OH Ostable stable Ounstable Ounstable OH OH HO. stable stable O unstable Ounstable

Many free radicals combine to form molecules that do not contain any unpaired electrons. The driving force for the radical- radical combination reaction is the formation of a new electron-pair bond. Consider the formation of hydrogen peroxide. 2 OH(g) → H₂O₂(g) Write Lewis formulas for the reactant and product species in the chemical equation. Include nonbonding electrons. OH(g) Select Draw Rings More / ||| ||| Erase Q2 Q H₂O₂(g) Select Draw Rings More 3 S H Erase Q2 Q Question Source: McQuarrie, Rock, And Gallogly 4e - General Chemistry Publisher: University Science B

The structure of Vitamin C (ascorbic acid) is shown below. As the name indicates, the molecule is somewhat acidic. Actually, one of the hydrogens on the four OH groups is much more acidic than the other three ones. Which one is the acidic hydrogen? Hints: To find the answer, you will again have to draw some resonance structures of the product formed after loss of H+. Consider the product after the loss of H+ for each of the OH groups. Only two of the OH groups have resonance structures after deprotonation; one of these two groups has a much better resonance structure than the other one (again after deprotonation). Note that the oxygen atom that is part of the five-membered ring has nothing to do with the problem.

For conjugate acid-base pair, identify the first species as an acid or a base and the second species as its conjugate base or conjugate acid. In addition, draw Lewis structures for each species, showing all valence electrons and any formal charges. Q) CH3OH, CH3OH2+

Explain why the following reaction is exothermic based on your knowledge of both bond enthalpy and exothermic reaction profile. Draw the exothermic reaction profile to help.   H2 +        Cl2                à                 2HCl                  DH = negative

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Write a line formula for all the free radicals that have the formula C5H11 and classify each as primary, secondary, or tertiary. Which one is the most stable?

Formation of ammonia from nitrogen and hydrogen is an exothermic process.  Which of the following statements is true about the bonds that are broken and formed during this reaction? N2(g) + 3H2(g) --->  2NH3(g) a.) products have lower PE because product bonds are weaker than reactants b.) products have higher PE because product bonds are stronger than reactants c.) products have higher PE because product bonds are weaker than reactants d.) products have lower PE because product bonds are stronger than reactants

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3) What is the [H'] when [OH]= 8.1 x 10°?