Which of the following statements is true for TLC when silica gel is used as the...

Which of the following statements is true for TLC when silica gel is used as the stationary phase? Note: More than one statement can be correct.

a) The more polar a compound, the more it will be attracted to the mobile phase.

b) Compounds with low polarity have higher Rf-values when solvents with lower polarity are used.

c) The higher the solvent polarity, the lower is the Rf-value of a compound.

d) The more polar a compound, the more it will be attracted to the stationary phase.

Solutions

Expert Solution

False: a) The more polar a compound, the more it will be attracted to the mobile phase. Because Silica Gel is a polar stationary phase. More polar compound will easily bind to the silica gel and cannot be easilt attracted by mobile phase.

True: b) Compounds with low polarity have higher Rf-values when solvents with lower polarity are used. Because low polarity compound will not bind the polar silica gel easily and can travel up in the TLC and will have higher Rf value (Rf value: = distance traveled by compound ÷ distance traveled by solvent front.)

False: c) The higher the solvent polarity, the lower is the Rf-value of a compound. As polarity of the solvent increase distance travel by the compound will increase and thereofre Rf-value will increase

True: d) The more polar a compound, the more it will be attracted to the stationary phase. Polar compound can easily attaracted by polar stationary phase i.e. silica gel

queen_honey_blossom answered 1 year ago

Next > < Previous

Related Solutions

An unknown mixture was analyzed using TLC on a silica gel plate and developed in 1:6...

An unknown mixture was analyzed using TLC on a silica gel plate and developed in 1:6 ethyl acetate:hexane, and gave 2 spots with Rf values of 0.6 and 0.5 respectively. 1)Would this be considered a good separation between the two? Briefly explain. 2)Which spot represents the more polar compound(s)? 3)Can you say for sure how many compounds are contained in the mixture? If so, how many are there? Briefly explain. 4)If not, what further conditions might be performed to determine...

When 2-propanol was used as the develop- ing solvent, two substances moved with the solvent front (Rf = 1) during TLC analysis on a silica gel plate.

1. When 2-propanol was used as the develop- ing solvent, two substances moved with the solvent front (Rf = 1) during TLC analysis on a silica gel plate. Can you conclude that they are identical? If not, what additional experiment(s) would you perform? 2.The Rf value of compound A is 0.34 when a TLC plate is developed in hexane and 0.44 when the plate is developed in diethyl ether. Compound B has an Rf value of 0.42 in hexane...

In thin-layer chromatography (TLC), the _________[ Select ] ["mobile phase", "stationary phase"] is usually silica gel...

In thin-layer chromatography (TLC), the _________[ Select ] ["mobile phase", "stationary phase"] is usually silica gel or alumina, and THE [ Select ] ["mobile phase", "stationary phase"] is usually an organic solvent or mixture of organic solvents. ANSWER THE QUESTION BY FILL IN THE BLANK 2 OPTIONS MOBIL PHASE OR STATIONARY PHASE. PLEASE DONT GIVE ANY WRONG ANSWERS AND THANKS FOR YOUR HELP !

Which of the following statements are true and which are false? Evaporation is used to decrease...

Which of the following statements are true and which are false? Evaporation is used to decrease the weight and volume of a liquid product. Concentration of a liquid food increases the shelf life of the food since it decreases the water activity. Falling film evaporators are not suitable for heat sensitive products. Agitated film evaporators are suitable for viscous liquids. Fruit juices are concentrated in falling film evaporators. Gelatin is concentrated in agitated film evaporators. Tomato juice is concentrated in...

Which of the following statements is NOT true when describing a proportionate mortality rate? A) When...

Which of the following statements is NOT true when describing a proportionate mortality rate? A) When calculating this measure, all deaths for the period of study are included in the denominator. B) This measure is expressed as a percentage of all deaths. C) This measure is used to describe the proportion of deaths in a defined population that is attributable to a specific cause. D) This measure is used to describe the total number of deaths in a defined population,...

Which of the following statements is true? A) A stable bond is formed when the potential...

Which of the following statements is true? A) A stable bond is formed when the potential energy is zero. B) When two atoms are very far apart, the potential energy is zero. C) The potential energy increases as attractive forces exceed repulsive forces. D) The bond length is the distance between the atoms when the potential energy is at its lowest point. E) The potential energy decreases as repulsive forces increase.

1. Which of the following statements is true of the accounting for finished goods when a...

1. Which of the following statements is true of the accounting for finished goods when a job is completed? Overhead costs are assigned to Finished Goods using a predetermined rate. Finished Goods is debited when goods are sold. The cost of completed units is credited to Work-in-Process and debited to Finished Goods. The costs of the completed job are retained in Work-in-Process until the proceeds are collectible for the job. 2. Slim Technology Inc. records the following amounts before reconciling...

Which of the following statements are true?

Which of the following statements are true? 1. Fats that contain more saturated fatty acid residues than unsaturated fatty acid residues are more likely to be solid at room temperature. 2. Triacylglycerols (triglycerides) contain ester bonds. 3. Saturated fats have lower melting points than do unsaturated fats. 4. Triacylglycerols (triglycerides) always contain three identical fatty acids. 5. Unsaturated fats are more likely than saturated fats to be liquid at room temperature.

Which of the following statements is true?

Which of the following statements is true?When a company goes bankrupt, common stockholders are the first to get paid.A preferred stock promises investors a fixed stream of dividend payments.Holders of preferred stocks have residual claim on the company’s assets and cash flows.Investing in a bond of a company is riskier than investing in a stock of the same company.

Which of the following statements is true?

Which of the following statements is true?The ask price a dealer quotes on a security is the price for which he is willing to sell the security.We can buy IBM shares from a stock broker.Any investor can buy securities from a private offering.A broker holds an inventory of securities

Subjects