How crude oil is refined? Explain the important fractions of petroleum along with their usage.

Posted Posted in Chapter No.16, Chemistry 10

No.6. How crude oil is refined? Explain the important fractions of petroleum along with their usage. Answer.   Crude   oil   is   refined   by   fractional   distillation   in   a fractionating tower. Important Fractions of Petroleum Each fraction is not a single compound. Rather each one is a mixture of hydrocarbons having different number of carbon atoms in it. […]

Write a note on fractional distillation of petroleum.

Posted Posted in Chapter No.16, Chemistry 10

  No.4. Write a note on fractional distillation of petroleum. Answer. The crude oil is refined in the refineries. Refining process is the separation of crude oil mixture into various  useful  products (fractions). It is carried out by a process called fractional distillation. The principle of fractional distillation is based upon separation of substances depending […]

Write a detailed note on Ammonia Solvay process.

Posted Posted in Chapter No.16, Chemistry 10

No.3. Write a detailed note on Ammonia Solvay process.  Answer. Principle of Solvay process lies in the low solubility of sodium bicarbonate at low temperature i.e. at 15°C. When CO2 is passed through an ammonical solution of NaCl called ammonical brine, only NaHCO3 precipitates. Na+(aq) + HCO3–(aq)         NaHCO3(s) Raw Materials: The raw materials needed for […]

What is the difference between crude oil and residual oil?

Posted Posted in Uncategorized

No.16. What is the difference between crude oil and residual oil? Answer. Crude oil is the dark brownish viscous liquid formed by decomposition of remains of dead plants and animals in the absence of air because of high pressure, temperature and bacterial effects. When it is heated in a furnace up to 400°C under high […]

Give the characteristics of polysaccharides.

Posted Posted in Chapter No.13, Chemistry 10

No.5. Give the characteristics of polysaccharides. Answer. Polysaccharides are macromolecular carbohydrates consisting of hundreds to thousands of monosaccharide. Examples of polysaccharides are starch and cellulose. They are amorphous solids. They are tasteless and insoluble in water. They are none reducing in nature, No.6. Where the proteins are found? Answer. Proteins are present in all living […]

Which elements are found in proteins?

Posted Posted in Chapter No.13, Chemistry 10

Test Yourself 13.2 (PROTEINS) No. i. Which elements are found in proteins? Answer. Proteins consist of carbon, hydrogen, oxygen, nitrogen and sulphur elements. No. ii. How amino acids are bonded with each other? Answer. The amino acids link through peptide linkage. Peptide linkage (bond) is formed by the elimination of water molecule between j the […]

Find the pH of 0.01M sulphuric acid?

Posted Posted in Chapter No.10, Chemistry 10

Problem.10.3. Find the pH of 0.01M sulphuric acid? Solution: Sulphuric acid is a strong dibasic acid. It ionizes completely and its one mole produces 2 moles of hydrogen ions. H2SO4(aq)   —————   2H+(aq) + SO42-(aq) Therefore,   0.01M   sulphuric   acid   will   produce   2   x   0.01M hydrogen ions. Hence, hydrogen ions concentration is [H+] = 2×10-2 M pH […]

Classify the following salts as soluble or insoluble salts:

Posted Posted in Chapter No.10, Chemistry 10

No.10. Classify the following salts as soluble or insoluble salts: Sodium chloride Silver nitrate iii. Lead chloride Copper sulphate Barium sulphate Ammonium chloride vii. Sodium carbonate viii. Calcium carbonate Ferric chl6ride Magnesium sulphate   Answer. Soluble Salt: Sodium chloride, Silver nitrate, Copper sulphate, Ammonium chloride, Sodium carbonate, Ferric chloride. Magnesium sulphate. Insoluble salt: Lead chloride, […]

How the insoluble salts are prepared?

Posted Posted in Chapter No.10, Chemistry 10

No.14. How the insoluble salts are prepared? Answer. In this method, usually solutions of soluble salts are mixed. During the reaction exchange of ionic radicals take place to produce two new salts. One of the salts is  insoluble and the other is soluble. The insoluble salt precipitates (solidify in solution). For example, AgNO3 NaCl        AgCl […]