Q. Why does dry HCl gas not change the color of dry litmus paper?
1) Blue litmus becomes dry in the presence of dry HCl gas
2) No H3O+ ions are present. Litmus changes colour only in the presence of H3O+ ions
3) HCI gas acts as a dehydrating agent
4) None of the above
Q. The odour of acetic acid resembles that of -
1) tomato
2) kerosene
3) vinegar
4) None of the above
Q. You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution respectively. Which of them will turn red litmus to blue?
1) Acid
2) Base
3) Distilled water
4) None of the above
Q. Which acid is described as HOOC COOH?
1) Oxalic acid
2) Acetic acid
3) Carbonic acid
4) None of the above
Q. Acids react with metal carbonates to liberate ____________ gas.
1) CO2
2) CO
3) H2
4) None of the above
Q. Some metal oxides react with acid as well as a base to produce salt and water. They are known as amphoteric oxides. Examples of amphoteric oxides are -
1) Al2O3 and ZnO
2) Al2O3 and CuO
3) CuO and ZnO
4) None of the above
Q. A form of matter has no fixed shape but it has a fixed volume. An example of this form of matter is -
1) krypton
2) kerosene
3) carbon steel
4) None of the above
Q. Nitrogen in the air -
1) Is essential for the body
2) Dilutes oxygen which is very active in pure form
3) Makes oxygen soluble in the blood
4) Decreases the density of air
Q. Which one of the following statements is not correct?
1) Most carbon compounds are good conductors of electricity
2) Bonding in organic compounds is covalent
3) Graphite is used as a lubricant
4) Diamond is an allotrope of carbon
Q. Which one of the following statements about fertilizers is not correct?
1) Urea is a phosphorous-containing fertilizer
2) Application of fertilizer to the soil increases the fertility of the soil
3) Urea can be prepared by the action of ammonia and carbon dioxide under high pressure and at high temperature
4) Urea contains more nitrogen than other fertilizers