The semiconductor industry manufactures integrated circuits in large vacuum chambers where the pressure is 1.0×10−10mm of hg.
(a) what fraction is this of atmospheric pressure? express your answer using two significant figures.
(b) at t = 10 ∘c, how many molecules are in a cylindrical chamber 50 cm in diameter and 50 cm tall?

(a): .

(b):  

Explanation:

Given, the pressure in the semiconductor industry which manufactures integrated circuits in large vacuum chambers,

We know,

1 mm of Hg = 133.322 Pa.

Therefore,

1 atmospheric pressure, = 101325 Pa.

Thus,

.

Now,

Volume of the cylindrical chamber is given by

Using the Ideal gas equation,

where,

Therefore,

a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.