Impact of weather factors on the speed of the reaction of formaldehyde formation above motorway overpasses.

The analysis of the actual air condition in the city of Kyiv in the areas of big overpasses and crossroads shows that the average annual concentration of formaldehyde more than 3 times exceeds the maximum permissible concentration (MPC) of this toxic substance. One of the most powerful sources of formaldehyde formation in the air of the city is motor vehicles. The role of weather factors in formaldehyde formation rate (K) depending on capacity of emissions of internal combustion engines has been analyzed in this article. The equation for determining rate constant has been obtained, which depends on the temperature in the city of Kyiv and on the value of effective energy activation of the mentioned process. The comparison of the calculated and measured values of the rate reaction constant in Observation Point (OP) No. 9 in the area of Leningradska square has been given. The conducted research gives the opportunity to assess and obtain forecasting data on atmospheric pollution and probability of smog situations emergence in Kyiv. The suggested methodology can be used for other cities in Ukraine where motor vehicles are the main indicator of photochemical smog emergence.