A signature made by graphite pencil is of weight `2 xx 10^-3 g `. Calculate the no. of carbon atoms in that signature.

A domain in ferromagnetic iron is in the form of a cube of side length 1 xx 10^-6 m . Estimate the number of iron atoms in the domain, the maximum possible dipole moment and magnetization of the domain. Given: density 7.9frac(g)(cm^3) , molecular mass of iron = 55 g/ mole. Assume each atom has a dipole moment of 9.27 xx 10^-24 Am^2 .

In three moles of ethane (C_2 H_6) . Calculate the following. Number of moles of carbon atoms.

Weight of 6.02 xx 10 ^20 molecules of H_2 is

The speed of light is 3 xx 10^8m//sec . Calculate the frequency of red light of wavelength of 6.5 xx 10^-7 m.

Ammonia and oxygen react at high temperature as : 4 NH_(3(g)) + 5O_2(g)rarr 4NO(g) + 6H_2O_(g) In an experiment, rate of formation of NO(g) is 3.6 xx 10^(-3) mol L^(-1). s^(-1) Calculate :-Rate of formation of water.

200 cm3 of an aqueous solution of a protein contain1.26g of the prote in.The osmotic pressure of such a solution at 300 K is found to be 2.57 xx 10^(-3) bar. Calculate the molarimass of-the protein.

A simplified model of hydrogen atom consists of an electron revolving about a proton at a distance of 5.3 xx 10^-1 1m. The charge on a proton is +1.6 xx 10^-19 C. Calculate the intensity of the electric field due to proton at this distance.

If the speed of light is 3.0 xx10^8 ms^-1 , calculate the distance covered by light to 2.00 ns.

2 xx 10^8 atoms of carbon are arranged side by side. Calculate the radius of carbon atom if the length of this arrangement is 2.4 cm.