Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

HIO_3 behaves as acid in water HIO_3 (aq) IO_3^- (aq) + H^+ (aq), with K_c = 0.1

ID: 994807 • Letter: H

Question

HIO_3 behaves as acid in water HIO_3 (aq) IO_3^- (aq) + H^+ (aq), with K_c = 0.17 at 25 degree C. What is the H^+ concentration in a solution that is initially 0.50 M HIO_3? 0.34 M 0.29 M 0.22 M 0.28 M The atmospheric pressure in the eye of a hurricane is found to be 26.6 in. of mercury, which is equivalent to 760 mm Hg 1.00 Times 10^5 Pa. 0.987 bar. 0.889 atm. 0.785 atm Given the following data for the reaction A rightarrow B, determine the activation energy, E_a, of the reaction to three significant figures. 6.89 J/mol 54.4 J/mol 57.3 J/mol 39.9 J/mol Oxidation refers to a gain in the number of protons an increase in oxidation number an increase in mass a decrease in oxidation number. What is the change in internal energy (Delta E) of a system when it is heated with 35.0 J of energy while it does 15.0 J or work? +35.0 J -20.0 J +50.0 J +20.0 J The half-life of radioactive carbon-14 is 5730 years. If the^14 C level in a sample of organic matter has been reduced to 0.200% of its original value, approximately how much time has passed? Radioactive decay follows first-order kinetics. 51,400 years 29,900 years 1650 years 9220 years Processes are always spontaneous when (H and S refer to the system). Delta H > 0 and Delta S > 0 Delta H

Explanation / Answer

Solution :-

Q14

HIO3   ------- > H+   + IO3^-

0.50                  0          0

-x                       +x        +x

0.50-x                x          x

Kc= [H^+][IO3^-] /[HIO3]

0.17 = [x][x]/[0.50-x]

0.17 * 0.50 –x = x^2

Solving for x we get

0.22 M= x

So the equilibrium concentration of the H+ = x = 0.22 M

Q15) 1 atm = 29.92 inHg

26.6 inHg * 1atm / 29.92 in Hg = 0.889 atm

So the answer is 0.889 atm that is option d

Q16) half life = 5730 yr

Rate constant K = 0.693 / half life

                              = 0.693 / 5730 yr

                              = 0.000121 yr-1

Activity reduced to 0.200 % of original

Ln([A]t/[A]o)= - K*t

Ln[0.200 /100] = -0.000121 yr-1 * t

-6.2146 = -0.000121 yr-1 * t

t = 6.2146/0.000121 yr-1

t= 51400 yr

so the answer is option a = 51400 yr                                                                                             

Q17) process is always spontaneous when the delta H is negative that is less than 0 and delta S is positive that is greater than 0

So the answer is option C

Q18) when the vaoltaic cell reaches the equilibrium then Ecell = 0 so the answer is option C

Q19) Using the Arrhenius equation we can calculate the activation energy

Ln [K2/K1] = Ea / R [(1/T1)-(1/T2)]

Ln[0.739/0.730] = Ea / 8.314 J per mol K [(1/250)-(1/450)]

0.01225 = (Ea/ 8.314 J per mol K ) *0.00178

0.01225*8.314 J per mol K / 0.00178 = Ea

57.3 J/mol = Ea

So the answer is option C

Q20) oxidation is loss of electrons which causes the increase in oxidation number so the answer is option B

Q21) system is heated means heat is added so q= 35.0 J and it does work 15.0 J means it is negative work done

So

Delta E = q + w

            = +35.0 J + (-15.0 J)

            = +20.0 J

So the answer is option D