Organic Chemistry Answers

How many number is bonds are in allenne

4. What is the purpose of adjusting the polarity?

5. Would benzoic acid dissolve better in water, or in ethanol? Explain why using the concepts discussed in this laboratory.

In a final very careful and correct recrystallization from acetone, benzoic acid (pure mp 122-122.3°C) was melted on a melting point machine immediately after vacuum filtration and washing, and found to have a melting point of 116-121°C. Why is the melting point not

122-122.3°C? Assume that there are no solid compounds present other than benzoic acid present, and suggest what may be present to affect melting point, and what role that presence does.

2. What are 2 advantages of using gravity filtration over vacuum filtration when removing a solid impurity from a hot mixture?

3. If iron filings were an impurity present along with the ASA in this experiment, at which point in the recrystallization procedure would they be removed completely from the ASA? (What slide numbers show this procedure?)

Using your polymeric materials data collection and sorting table you or your class/team produced, please answer the following questions on a separate sheet of paper.

From the polymeric material samples collected:

1.Which polymeric material was most commonly collected?

2.What percentage of the total collection did the most common material represent?

3.Which polymeric material was the least common collected?

4.What percentage of polystyrene materials were collected?

5.What was the most common application collected for polyethylene terephthalate materials collected?

6.Ranking the polymeric materials collected from the most common to least common, where did high-density polyethylene rank in your sample?

1.Addition of HBr to H2C=CH2

2.Addition of Br2 to Ethyne

3.CH3CH=CHCH3 + Cl2

4.Cyclobutene + Br2

5. + I2

Illustrate  the different structural  isomers  of  the following molecules.

1. C6H14

2. C5H11Cl

3. C7H7I

containing benzene

ring

4. C4H8O

5. C4H8O2

Give balanced equation for the following reactions:

a. Zinc to sodium zincate -using an alkali

b. Water gas to hydrogen – industrially

c. Sodium aluminate from aluminium

d. Hydrogen from boiling water using a divalent metal

e. Hydrogen from Steam using a metal and the reaction is

reversible

f. Balanced equation for the laboratory preparation of

hydrogen

g. Steps followed in Bosch process

h. Magnesium chloride from HCl

i. Water gas from water

j. Aluminium sulphate from aluminium

Why do we use H2SO4 with oxidising agent K2Cr2O7 during a Chemical Reaction.

A sample of meat scrap weighing 2.000 g is digested with concentrated sulfuric acid and a catalyst. The resulting solution is made alkaline with NaOH and the liberated ammonia distilled into 50.00 mL of 0.6700 N HCl. The excess acid then requires 30.10 mL of 0.6520 N NaOH for neutralization. What is the percentage of the protein in the meat? The Kjeldahl factor is 6.25.

A 0.7500-g carbonate mixture was dissolved in water and then titrated with 0.2000 N HCl, requiring 24.20 mL for the phenolphthalein endpoint. In another flask, 40.20 mL of the acid was required to reach the bromocresol green endpoint. Calculate the %NaOH, %NaHCO₃, and %Na₂CO₃ in the mixture.