Which of the following is a chemical change? a water vapor in the air turns to liquid water in the form of rain b the oxygen in the air forms ozone in presence of uv rays c dust and soot particles being suspended in the air d sulphur dioxide being released in the air

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.

> b takes place in the gas phase in an isothermal tubular reactor. the feed is one mole of a per one mole of c, an inert. the entering temperature and pressure are 427°c and 10 atm, respectively. the gas constant r = 0.08206 atm · l/mol · k.