7. Balance the following equation. What is the coefficient for Oxygen?* C. H. +0,-> C0, +H20
2
4
5
8

8. Pentane (CsH22) undergoes a combustion reaction. What is the coefficient
required in front of pentane in its balanced equation? *
C. H2 +0,-> C0, + H2O
5
4
2
1

I know it’s tho questions but PLEASE PLEASE help me it’s for a test and I don’t wanna fail I would REALLY appreciate it if someone could help me with this thanks youu !!!

Zoe is investigating the composition of substance a, an unknown substance. using chemical processes, she analyzes substance a and determines it is composed of sodium, oxygen, and hydrogen atoms in a ratio of 1 : 1 : 1. what is substance a? a. a compound b. an element c. a heterogeneous mixture d. a homogeneous mixture

7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation. 8. when a 2.5 mol of sugar (c12h22o11) are added to a certain amount of water the boiling point is raised by 1 celsius degree. if 2.5 mol of aluminum nitrate is added to the same amount of water, by how much will the boiling point be changed? show all calculations leading to your answer or use 3 – 4 sentences to explain your answer. 9. if 5.40 kcal of heat is added to 1.00 kg of water at 100⁰c, how much steam at 100⁰c is produced? show all calculations leading to an answer. 10. the freezing of water at 0⁰c can be represented as follows: h2o (l) ↔ h2o(s) the density of liquid water is 1.00 g/cm3. the density of ice is 0.92 g/cm3. in 3 – 4 sentences explain why applying pressure causes ice to melt.

Select the correct location on the image identify the element that humans need to breathe. 2015 er r ights reserved