Soil is the surface layer of the land. It includes a number of factors which collectively form the soil complex. Discuss the following:
How the distribution of vegetation depends upon the nature of soil?

Soil is the surface layer of the land. It includes a number of factors which collectively form the soil complex. Disease the following: What is significance of presence of humus in the soil?

Soil is the surface layer of the land. It includes a number of factors which collectively form the soil complex. Disease the following: What is soil profile?Write one main feature of each of various soil layers.

In which one of the following habitats, does the diurnal temperature of soil surface vary most?

Read the given passage and answers following questions : Thomas Graham in 1861, during his work on diffusion found that certain substances such as gelatin, albumin, glue,etc. Diffused at very low rate and were called colloids. The colloid particles have the size in the range of 1 to 100nm consisting of dispersed phase and dispersion medium. The dispersed phase or dispersion medium may be solid, liquid or even a gas. Depending upon the nature of dispersion medium or dispersed phase, 8 types of systems are possible except for a gas dispersed in another gas because the gases are completely miscible with each other. The substances which have strong interaction with the dispersion medium are called lyophilic colloids while those which do not pass into colloidal state readily are called lyophobic colloids. Lyophobic sols are much less stable and are irreversible. Answer the following questions : How many types systems are possible depending upon the nature of dispersion medium?

Read the given passage and answers following questions : Zeolites are alumino-silicates that are micro-porous in nature. Zeolites have a honeycomb like structure, which makes them shape-selective catalysts. They have an extended 3D-nelwork of silicates in which some silicon atoms are replaced by aluminium atoms, giving them an Al-O-Si framework. The reactions taking place in zeolites are very sensitive to the pores and cavity size of the zeolites. Zeolites are commonly used in the petrochemical industry. A catalytic reaction which depends upon the pore structure of the catalyst and on the size of the reactant and the product molecules is called shape-selective catalysis. For example, catalysis by zeolites is a shape selective catalysis. The pore size present in the zeolites ranges from 260-740 pm. Thus, molecules having a pore size more than this cannot enter the zeolite and undergo the reaction. Upon which factor a catalytic reaction depends ?

In an experiment to estimate the size of a molecule of oleic acid 1mL of oleic acid is dissolved in 19 mL of alcohol. Then 1 mL of this solution is diluted to 20 mL by adding alcohol. Now 1 drop of this diluted solution is placed on water in a shallow trough. The solution spreads over the surface of water forming one molecule thick layer. Now, lycopodium powder is sprinkled evenly over the film and its diameter is measured. Knowing the volume of the drop and area of the film we can calculate the thickness of the film which will give us the size of oleic acid molecule. Read the passage carefully and answer the following questions : How will you calculate the volume of n drops of this solution of oleic acid ?

Give information as asked about following mineral nutrient is plants: Phosphorus The form in which it is absorbed from soil,

Radioactive disintegration is a first order reaction and its rate depends only upon the nature of nucleus and does not depend upon external factors like temperature and pressure. The rate of radioactive disintegration (Activity) is represented as -(dN)/(dt)=lambdaN Where lambda= decay constant, N= number of nuclei at time t, N_(0) =intial no. of nuclei. The above equation after integration can be represented as lambda=(2.303)/(t)log((N_(0))/(N)) Calculate the half-life period of a radioactive element which remains only 1//16 of its original amount in 4740 years: a) 1185 years b) 2370 years c) 52.5 years d) none of these

Radioactive disintegration is a first order reaction and its rate depends only upon the nature of nucleus and does not depend upon external factors like temperature and pressure. The rate of radioactive disintegration (Activity) is represented as -(dN)/(dt)=lambdaN Where lambda= decay constant, N= number of nuclei at time t, N_(0) =initial no. of nuclei. The above equation after integration can be represented as lambda=(2.303)/(t)log((N_(0))/(N)) Half-life period of U is 2.5xx10^(5) years. In how much time will the amount of U^(237) remaining be only 25% of the original amount ? a) 2.5xx10^(5) year b) 1.25xx10^(5) years c) 5xx10^(5) years d) none of these