That depends. What kind of change are you talking about? But
Mass<span> through chemical </span>change<span> stays the same as well. Example: burning paper, the ash left behind is not all of the </span>mass<span> of the reactants, Carbon dioxide, and other </span>substances<span> also makeup</span>mass<span> but just is not seen
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Answer:
1,Iodine solution is used to test leaves for the presence of starch. ...
2.After a few minutes, the parts of the leaf that contain starch turn the iodine from brown to blue/black.
3.The leaf on the left is a variegated leaf
Explanation:
Epsom salt is MgSO4.
We assume x water of hydration in the crystalline form.
Molecular mass of MgSO4 = 24+32+4*16=120
Molecular mass of MgSO4.xH2O = 120+18x
By proportion,
2.000/0.977 = (120+18x)/120
Cross multiply
0.977(120+18x) = 120*2.000
from which we solve for x
17.586x+117.24 = 240
x=122.78/17.586
=6.980
Answer: there are 7 water of hydration in Epsom salt, according to the experiment.
Note: more accurate (proper) results may be obtained by using exact values (3-4 significant figures) in the molecular masses. However, since water of hydration is the nearest integer, using approximate values (to at least two significant figures) suffice.
