Science 7 Practice Worksheet : Branches of Science 1st Quarter, A. Y. 2014 – 2015
Name _ Class _ Teacher's Name _
1. Complete the statement below.
Score _ Date _
Science is the _ study about the _ and _ world around us through _, _,and _. Through this study, scientists develop a body of _ _ that helps us understand the world around us.
2. Identify the branches of Science described in the statements below. Misspelled answers will be considered wrong.
_a. study of the moon, stars, planets and other bodies in space _b. study about the earth's layers and its history
_c. a branch of life science that studies all the living things and their internal processes _d. a branch of life science that focuses on the study of animals _e. a branch of geology that studies about earthquakes and earth's crust's movement _f. study of the weather and the condition of the atmosphere
_g. study of the ocean, seas and all marine life
_h. study of the relationship between the earth's physical features and the forces that
make or change them
_i. study of matter and substances and the changes that happen when these subtances
combine or react with other substances _j. a branch of biology that studies on plants

first, consult an activity series chart to determine if al is more reactive than fe. it is, so it will replace the fe. now, one can continue with the problem.

next, make sure you have a correctly balanced equation.

3feo + 2al ==> 3fe + al2o3

now, determine which reactant (feo or al) is in limiting supply.

moles feo present = 125 g x 1 mole/71.8 g = 1.74 moles

moles al present = 25.0 g x 1 mole/26.98 g = 0.927 moles

since from the balanced equation, it take 3 mol feo for every 2 mol al, al will be limiting.

you can determine this simply by dividing moles of each by their coefficient in the balanced equation. for example: 1.74/3 = 0.58 and 0.927/2 = 0.464. al is less, so it is limiting.

finally, using the stoichiometry in the balanced eq. determine mass of fe that can be produced from 0.927 moles of al.

0.927 moles al x 3 moles fe/2 moles al x 55.8 g/mole = 77.6 g

  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-

what is the question here. i think you messed up.