UNIT 1 REVIEW Date: 3-3-2021
Name:
Complete this review to check your understanding of the unit.
Use the photo of the test tube to answer Questions 1-2.
1. The liquids in the test tube float on top of each other in layers.
The least / most dense liquids are on the bottom. The liquids
lower in the tube have less / more mass per unit volume than
the liquids in the upper part of the tube.

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-

the right answer is c i just did the question.