Which compound is shown in the illustration?

a hydrocarbon

Explanation:

1. Functional group is a specific group of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules.

2. A halogen is the name of group 17 elements containing fluorine, chlorine, bromine, iodine and astatine.

3. A hydrocarbon is a compound containing carbon and hydrogen. Example: alkanes, alkenes and alkynes.

Propane is an alkane with molecular formula .

4. An ester is a functional group .

mg3n2 is known as magnesium nitride

explanation:

i don't think ke is an compound

a mercury barometer is a device that uses the physical properties of mercury in a tube to measure barometric pressure. mercury barometers are used for : -

1. measurement of atmospheric pressure  

2. determining the altitude of a place

3. weather forecasting

4. calibration and checking of aneroid barometers

5. application in fluid mechanics

6. measurement of pressure in aircrafts

7. surface weather analysis

8. preparation of barographs

9. usage in physical sciences like physics, astronomy & chemistry

10. preparation of aircraft altimeters

characteristics of mercury barometer : -

1.used to define and measure atmospheric pressure.

2.on the average at sea level the column of mercury rises to a height of about 760 mm.

3.this quantity is equal to 1 atmosphere.

4.it is also known as standard atmospheric pressure.

5.a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.