An ideal gas in a cylindrical container of radius r and height h is kept at constant pressure p. the bottom of the container is maintained at temperature t0 while the top at temperature t1. assuming a linear temperature distribution along the cylinder, calculate the total mass of gas within the container.

Explanation:

The gas ideal law is  

PV= nRT (equation 1)

Where:

P = pressure  

R = gas constant  

T = temperature  

n= moles of substance  

V = volume  

Working with equation 1 we can get  

The number of moles is mass (m) / molecular weight (mw). Replacing this value in the equation we get.

 or  

  (equation 2)

The cylindrical container has a constant pressure p  

The volume is the volume of a cylinder this is

Where:

r = radius  

h = height  

(pi) = number pi (3.1415)

This cylinder has a radius, r and height, h so the volume is  

Since the temperatures has linear distribution, we can say that the temperature in the cylinder is the average between the temperature in the top and in the bottom of the cylinder. This is:  

Replacing these values in the equation 2 we get:

  (equation 2)

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.