Read the following and answer any four questions from (Q1) to (Q5).
Q4. Which of the following reactions represents a combination reaction?
Q5. Complete the following statements by choosing correct type of reaction for X and Y.
Statement 1: The heating of lead nitrate is an example of ‘X’ reaction.
Statement 2: The burning of magnesium is an example of ‘Y’ reaction.
Read the following and answer any four questions from (Q1) to (Q5).
pH is quite useful to us in a number of ways in daily life. Some of its applications are:
Control of pH of the soil : Plants need a specific pH range for proper growth. The soil may be acidic, basic or neutral depending upon the relative concentration of H* and OH-. The pH of any soil can be determined by using pH paper. If the soil is too acidic, it can be corrected by adding lime to it. If the soil is too basic, it can be corrected by adding organic manure which contains acidic materials.
Regaining shine of a tarnished copper vessel by use of acids : A copper vessel gets tarnished due to formation of an oxide layer on its surface. On rubbing lenion on the vessel, the surface is cleaned and the vessel begins to shine again. This is due to the fact that copper oxide is basic in nature, which reacts with the acid (citric acid) present in lemon to form a salt (copper citrate) which is washed away with water. As a result, the layer of copper oxide is removed from the surface of the vessel and the shining surface is exposed
Self-defence by animals through chemical warfare : Stings of bees and ants contain methanoic acid. When stung, it causes lot of pain and irritation. This can be cured by rubbing the affected area with mild base like baking soda.
Q1. When black Copper Oxide place in a beaker is teated with dilute HCL. iits colour changes to
Q2. P is an aqueous solution of acid and Q is an aqueous solution of base. When these two are diluted separately, then
Q3. Which of the following acids is present in bee sting?
Q4. Sting of ant can be cured by rubbing the affected area with soap because
Q5. The pH of soil X is 7.5 while that of soil Y is 4.5. Which of the two soils, should be treated with powdered chalk to adjust its pH?
Read the following and answer any four questions from (Q1) to (Q4).
Food, clothes, medicines, books, or many of the things are all based on this versatile element carbon. In addition, all living structures are carbon based. The earth’s crust has only 0.02% carbon in the form of minerals. The element carbon occurs in different forms in nature with widely varying physical properties. Both diamond and graphite are formed by carbon atoms, the difference lies in the manner in which the carbon atoms are bonded to one another. Carbon has the unique ability to form bonds with other atoms of carbon, giving rise to large molecules. This property is called catenation.
Q1. From the given alternatives, whose chemical and physical properties are not same?
Q2. Which of the following statements is not correct?
Q3.Which of the following are isomers?
