Consider the reaction: 2NO(g) + O2(g) + 2NO2(g)
Given an initial mass of 16.07 g NO, an excess of Oz, and assuming that all of the reactant is converted to product(s), and none is lost, calculate the mass (g) of NO2 produced
by the reaction.

in cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. a contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.

explanation:

a corroding iron, if that's one of your choices