Chemical symbols stand for?

Answer Explanation:

If it is like H, or O or N or Na or Cl, those are the elements. Those are on the Periodic table. pH is the acidity and basicity of a substance, how acidic or basic(caustic) it is. mol is Moles. kPa is kilopascals. STP is standard temperature and pressure, at 0*C(Celsius), or 273.15 K(Kelvin), and 101,325 pascals, or 101.325 kilopascals.

Avagadro's Number is 6.022x10^23, the number of atoms in a mole. The Ideal Gas Law is P(Pressure in kPa) times V(Volume in L, liters) equals n(number of moles of gas) times R(the universal gas constant, or 8.3145 (L kPa/K mol) or 8.3145 liters kilopascals per Kelvin mole. that is just a few of them.

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.

it's all four options.