Consider the following mechanism for the reaction between nitric oxide and ozone:
1. O3 (g) + NO (g) > O (g) + NO3 (g)
2. O (g) + O3 (g) > 2O2 (g)
3. NO3 (g) + NO (g) > 2NO2 (g)
A. Write the chemical equation of the overall reaction.
B. Are there any intermediates in this mechanism.
C. If there are intermediates, write down their chemical formulas.

A .  2 O₃(g) + 2 NO   ⇒  2 O₂ (g) + 2 NO₂(g)

B . Yes

C.   O and NO₃

Explanation:

A. The overall reaction is obtained by adding the individual steps in the reaction mechanism where we will get the reactants and product and the intermediates will cancel.

Thus, adding 1+ 2 +3 we get

2 O₃(g) + 2 NO   ⇒  2 O₂ (g) + 2 NO₂(g)

B. The reaction intermediates are those that are produced from the initial and/or subsequent steps and are consumed later on in the reaction mechanism, but  are neither reactants nor products, they just participate.

From this definition it follows that O(g) and NO₃ are reaction intermediates.

C. O and NO₃

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.

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.