Balance the following equations: (a) k+o2 -> ko2 (b) fecl2+na2sio3 -> nacl + fesio3 (c) f2+alcl3 -> alf3 + cl2 (d) ca(s) + br2(l) -> cabr2(s) (e) p4(s) + o2(g) -> p4o10(s) (f) sb2s3(s) + hcl(aq) -> sbcl3(s) + h2s(g) (g) fe2o3(s) + c(s) -> fe(s) + co(g)

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.

gas

explanation:

smoke is the matter of a gas