9. A combination of sand, salt, and water is an example of a A) homogeneous mixture B) heterogeneous mixture C) compound D) pure substance E) solid 10. Forthe following reaction Chldh +Oz ? CO2 + 11,0 what is the coefficient of oxygen? a. 2 b. 4 c. 6 d. 8 e. None of the above Solution 9) Salt, sand and water mixture contains two different phases. liquid phase and solid phase. and moreover they dont mix and form separate phases. So, this is example of heterogeneous mixture. (B) 10) Balance the reaction : C 3 H 4 O2 + O 2 -----------> CO 2 + H 2 O balance the reaction for Carbon , C 3 H 4 O2 + O 2 -----------> 3 CO 2 + H 2 O balance the reaction for hydrogen, C 3 H 4 O2 + O 2 -----------> 3 CO 2 + 2 H 2 O now balance the reaction for oxygen, C 3 H 4 O2 + 3 O 2 -----------> 3 CO 2 + 2 H 2 O So, the answer is 3 and option is none of the above. .