Question

In: Chemistry

What kind of shift occurs when you add KNO3 to the equilibirum reaction: Fe3+ + SCN-...

What kind of shift occurs when you add KNO3 to the equilibirum reaction: Fe3+ + SCN- <=> FeSCN2

i know the reaction turns into an orange color

Solutions

Expert Solution

Fe3+ ion and SCN- react with each other to form a red complex ion, [FeSCN]2+. If you use very dilute solutions of Fe3+ and SCN- then the color of the product will be faint reddish-orange. In this experiment, if you use much more concentrated solutions , the product solution is a deep red (almost the color of blood).

Fe3+(colorless) + SCN- (colorless) = [FeSCN]2+ (blood red)

In this system, we can tell in which direction the equilibrium shifts when a change is made by monitoring the intensity of color of the system. If the system gets darker red in color, then the equilibrium must be shifting to the right (toward producing more of the colored product). If the color of the system gets fainter (or disappears altogether), the equilibrium must be shifting toward the left (toward the colorless components). You had to be very observant on this part to see the change in intensity of the red color when a drop of reagent was added: if you waited too long, the localized change in color as the droplet enters the equilibrium reaction would fade out.

The additional reagent KNO3 can only change the colour if it can form precipitate in this solution. If we add KNO3 to this solution than Fe(NO3)3 or KSCN can form . But here both Fe(NO3)3 and KSCN are soluble and do not form precipitate . So, according to me there should be not change in intensity of colour. Hence, we can say reaction shifts to left.

But if you are saying that reaction turn into orange color (less intense colour than deep red ) then it means reaction is reactant favoured. So,


Related Solutions

What kind of reaction occurs when anti-tTG is bind to the tissue transglutaminase? What kind of...
What kind of reaction occurs when anti-tTG is bind to the tissue transglutaminase? What kind of biosensor can measure their reaction? How will the measurement be made for their reaction?
Consider the following reaction : Fe3+ (aq) + SCN- (aq) ---> Fe(SCN)2+ (aq) Starting with 4.00...
Consider the following reaction : Fe3+ (aq) + SCN- (aq) ---> Fe(SCN)2+ (aq) Starting with 4.00 mL of .200 M Fe3+ (aq) in a cuvette, 0.10 mL increments of 0.00100 M SCN- (aq) will be added. Assume that because [Fe3+ (aq)] >> [SCN- (aq)], the [Fe(SCN)2+] concentration can be calculated from the limiting reagent, SCN-. Calculate [Fe(SCN)2+]. Volume .00100 M KSCN mL [Fe(SCN)2+] (M) .10 .20 .30 .40 .50 .60 .70 .80 .90 1.00
Assume that at some temperature, Kc= 100 for the reaction: Fe3+ (aq) + SCN- (aq) ⇌...
Assume that at some temperature, Kc= 100 for the reaction: Fe3+ (aq) + SCN- (aq) ⇌ FeSCN2+. Calculate the equilibrium concentration of FeSCN2+ if 100 mL of 0.24 M Fe(NO3)3 are mixed with 100 mL of .24 M KSCN. Show your work. Specifically, how do I determine the initial amounts? Is it just .24 or .24/100mL? And do I need to convert to Liters or anything?
balance redox reaction that occurs in acidic conditions. what are coefficients for H + & Fe3+...
balance redox reaction that occurs in acidic conditions. what are coefficients for H + & Fe3+ once reaction is balanced? write it as H+=#; Fe +3 = # Fe2+(aq)+Mn04-(aq) -> Fe3+(aq)+Mn2+(aq)
The reaction Fe3+(aq)+ SCN-(aq)FeSCN2+(aq)is initiated by mixing 1.50 mL of 0.0060 M iron nitrate (Fe3+) with...
The reaction Fe3+(aq)+ SCN-(aq)FeSCN2+(aq)is initiated by mixing 1.50 mL of 0.0060 M iron nitrate (Fe3+) with 0.75mL of 0.0020 M KSCN (SCN-) and enough water to give a total volume of 3.0 mL in a cuvette. The reaction goes to equilibrium with a final concentration of 1.55 x 10-4M FeSCN2+. Calculate Kc at 25°C for the reaction. Answer on the back side of this page. (Hint:calculate the initial concentrations of Fe3+ and SCN in the cuvette and use an ICE...
Consider the following reaction: Fe3+(aq)+SCN−(aq)⇌FeSCN2+(aq) A solution is made containing an initial [Fe3+] of 1.2×10−3 M...
Consider the following reaction: Fe3+(aq)+SCN−(aq)⇌FeSCN2+(aq) A solution is made containing an initial [Fe3+] of 1.2×10−3 M and an initial [SCN−] of 7.8×10−4 M . At equilibrium, [FeSCN2+]= 1.7×10−4 M .Calculate the value of the equilibrium constant (Kc).
Consider the following reaction: Fe3+(aq)+SCN−(aq)⇌FeSCN2+(aq) A solution is made containing an initial [Fe3+] of 1.1×10−3 M...
Consider the following reaction: Fe3+(aq)+SCN−(aq)⇌FeSCN2+(aq) A solution is made containing an initial [Fe3+] of 1.1×10−3 M and an initial [SCN−] of 8.2×10−4 M. At equilibrium, [FeSCN2+]= 1.8×10−4 M . Part A Calculate the value of the equilibrium constant (Kc). Express your answer using two significant figures. Kc=
Consider the reaction represented by the equation: Fe3+(aq) + SCN-(aq) <====> FeSCN2+(aq) ddddd §Trial #1: 6.00...
Consider the reaction represented by the equation: Fe3+(aq) + SCN-(aq) <====> FeSCN2+(aq) ddddd §Trial #1: 6.00 M Fe3+(aq) and 10.0 M SCN-(aq) are mixed at a certain temperature and at equilibrium the concentration of FeSCN2+(aq) is 4.00 M. What is the value for the equilibrium constant for this reaction? k=0.333 §Trial #2: Initial: 10.0 M Fe3+(aq) and 8.00 M SCN−(aq) (same temperature as Trial #1) Equilibrium:    ?   M FeSCN2+(aq)                       answer 5.00 M FeSCN2+ how can I solve trial #2??
Using your average Keq value (.3948), please calculate what the equilibrium concentrations of Fe3+ , SCN-...
Using your average Keq value (.3948), please calculate what the equilibrium concentrations of Fe3+ , SCN- , and FeSCN2+ in a solution made by combining 10.00mL of 0.0020M Fe(NO3)3 and 10.00mL of 0.0020M KSCN.
The water-gas shift reaction (CO + H­2O à CO2 + H­2) occurs in a series of...
The water-gas shift reaction (CO + H­2O à CO2 + H­2) occurs in a series of two reactors. An equimolar mixture of steam and CO (stream 1) enters the first reactor. The product stream from the first reactor (stream 3) and an additional stream (stream 3) containing pure steam enter the second reactor. The fractional conversion of CO in the first reactor is 0.610, and the fractional conversion of CO in the second reactor is 0.790. The product stream has...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT