ctevt exam qoestion 2079 chemistry paper

1     Define chemical symbol and chemical formula  with example 

Ans......           Chemical symbol: shorthand representation of an element's name (e.g. C for carbon, O for oxygen)

Chemical formula: shorthand representation of a molecule or compound (e.g. H2O for water, C6H12O6 for glucose)

A chemical symbol is a shorthand representation of the name of an element in the periodic table. It consists of one or two letters, with the first letter always capitalized, and the second letter, if present, in lowercase. For example, the chemical symbol for carbon is "C", for oxygen is "O", and for gold is "Au".

In summary, chemical symbols represent individual elements, while chemical formulas represent compounds or molecules.

2.     among oxygen and nitrogen which has higher ionization value and why ? 

ans.   Ionization energy is the energy required to remove an electron from an atom or ion in the gaseous state. Oxygen has a higher ionization energy than nitrogen because oxygen has a smaller atomic radius and a greater nuclear charge than nitrogen. This means that the electrons in an oxygen atom are held more tightly by the nucleus and are more difficult to remove than the electrons in a nitrogen atom.

Oxygen has a higher ionization energy than nitrogen due to its smaller atomic radius, greater nuclear charge, and greater electron stability.

3.   show lewis structure    of   

  h2 so4 and NH3

4.     Nitrogen diffuses faster than carbon dioxide.

Diffusion is the process by which particles move from an area of high concentration to an area of low concentration. The rate of diffusion depends on several factors, including the size and mass of the particles, temperature, pressure, and concentration gradient.

Therefore, nitrogen diffuses faster than carbon dioxide due to its smaller molecular weight and simpler molecular structure.

5.   state and explain Graham's law of diffusion 

ans..    Graham's law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of its molecular weight.

In simpler terms, this means that lighter gases will diffuse more quickly than heavier gases under the same conditions.

The law is named after Scottish chemist Thomas Graham, who studied the diffusion of gases in the mid-19th century. He found that the rate of diffusion of gases is related to their molecular weight, and that lighter gases such as hydrogen and helium diffuse more quickly than heavier gases such as oxygen and nitrogen.

The law can be expressed mathematically as:

Rate1/Rate2 = sqrt(M2/M1)

where Rate1 and Rate2 are the rates of diffusion of gases 1 and 2, and M1 and M2 are their respective molecular weights.

Graham's law of diffusion is important in a variety of fields, including chemistry, physics, and biology. It helps explain why certain gases diffuse more quickly than others, and has practical applications in areas such as gas chromatography and gas separation techniques.