2. Chlorine. In a clean, 150-mm test tube, place 2 mL of a 5% sodium nypocmonte
ID: 1043106 • Letter: 2
Question
2. Chlorine. In a clean, 150-mm test tube, place 2 mL of a 5% sodium nypocmonte NaCIO, solution (commercial laundry bleach) and 10 drops of cyclohexane. Agi 7a tate the mixture (Figure 11.5). Which layer is the cyclohexane layer?3 Add -10 drops of 6 M HCI. (Caution: 6 M HCl is very corrosive. Wash immediately from the skin.) Swirl or agitate the mixture (with a stirring rod) so that the HCl mixes with the NaCIO solution. Note the color of the chlorine in the cyclohexane layer. Record your observation. Do not discard save for Part C.l. 3. Bromine. In a second, clean test tube, place 2 mL of 3 M KBr solution and 3 drops of cyclohexane. Add 5-10 drops of 8 M HNO3. (Caution: HNO attacks skin tissue: flush the affected area immediately with water.) Agitate or swirl the mixture so that the 8 M HNO, mixes with the KBr solution. Place the test tube ina hot water bath to increase the reaction rate. Note the color of the bromine in the cyclohexane layer. Record but do not discard--save for Part C.2. 4. Iodine. Repeat Part B.3 in a third test tube, substituting 3 M KI for 3 M KBr. Record. Compare the appearance of the three halogens dissolved in the cyclo- nts ger hexane Save for Part C.3.Explanation / Answer
It seems like you want to know about the observations.
2) NaOCl is water soluble while cyclohexane is not. The cyclohexane layer is on top of the aqueous NaOCl layer. Now, NaOCl reacts with HCl as below.
NaOCl + 2 HCl ---------> NaCl + Cl2 + H2O
The Cl2 move to the cyclohexane layer, giving a pale color to the layer. The rest of the species are water soluble and remains in the aqueous layer below.
3) The cyclohexane layer is initially above the aqueous KBr layer. Bromine (Br2) is produced by the action of HNO3 on KBr as below.
KBr + HNO3 ---------> KNO3 + HBr
HBr decomposes on heating giving Br2 which moves to the cyclohexane layer, giving a reddish color to the layer.
2 HBr -------> H2 + Br2
4) As in (3) above, we have aqueous KI below the organic cyclohexane layer. HI is initially formed which decomposes producing I2. The I2 moves to the cyclohexane layer, giving a purple coloration to the layer.
KI + HNO3 --------> KNO3 + HI
2 HI --------> H2 + I2
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.