EdExceL SCIENCE ANSWER KEY

For the last handout:

1.  C
2.  B
3.  B
4.  B
5.  C
6.  B
7.  B
8.  C
9.  B
10.  D
11.  (a)  It gives shape.  (b)  It supports the body.  (c)  It protects organs inside the body.
12.  iron & sand - use a magnet, stones & sand - use a seive, sand & water - filtration, salt & water - evaporation
13.  Advantage:  It doesn't give off harmful emmissiona and readily availbale
       Disadvantage:  It is expensive and not easy to replace gasoline.
14.  (a)  water resistance  (b)  streamlined, faster (counter react the water resistance)
15.  C
16.  D
17.  A
18.  B
19.  C
20.  A
21.  B
22.  A
23.  A
24.  C
25.  (a)  asexual rreproduction  (b)  Only one parent plant is required.  Young plants are identical to the parents.  (good traits are always passed on)
26.  (a)  Metal R - Metal S  - Metal P - Metal Q
       (b)  copper + iron sulfate
27.  (a)  Artificial satellite are man made satellite and launch into the orbit by using rockets.
       (b)  It is used in scientific research & to study universe.
28.  C
29.  D
30.  A
31.  B
32.  B
33.  C
34.  D ( 39 - 84) Period - horizontal & Group - vertical
35.  C
36.  B
37.  D
38.  As the intensity of the light is increasing, there will be a point that the rate of photosynthesis will be constant after a certain point is already reached.
39.  (left to right/ top to bottom)
       (a)  FF     Ff
              Ff     ff
       (b)  ff (cystic fibrosis)
40.  (a)  100 g
       (b)  For a complete reaction, calcium chloride, hydrogen gas & carbon dioxide should be produced.  In this case, water is produced instead.  even if, the mass should still be 100 g.  If there will be losses in the reaction, it is possible that the reaction does not follo Law of Conservation of Mass such exampple is escape of gas or spillage of the sample.
41.  (a) & (b) - See picture.
       (c)  Moment of force = F X d = (5 N) (0.2 m) = 1 N-m
42.  (a)  Use 1 grdaient = 2 cm
       (b)  i.  See picture.
              ii.  Before disregarding, run another trial.
       (c)  i.  See picture.
              ii.  By using the projected line, the change in length for 100 g is 36 cm.
43.  (a)  Use goggles, gloves & labcoat.  Handle acid with care.
       (b)  The bigger the surface are, the longer the time it will react.
       (c)  If diluted acid will be used, it will slow down the reaction time.
44.  (a)  To know the effect of the different proportion of N, P, K in plant growth.
       (b)  The fertilizer that will produce the most pepper is fertilizer B (low in N & high in P & K)
       (c)  same condition (same amout of water & fertilizer)  & same location (sunlight)
       (d)  i.  amount of fertilizer
              ii.  plant growth
       (e)  That plant will serve as the CONTROL variable where all samples will be compared to.
         


God bless in your EdExceL examination.