Answer:
Three half lives.
Explanation:
Given data:
Number of half lives passed = ?
Amount of parent isotope left = 12.5%
Solution:
At time zero = 100%
At 1st half life = 100%/2 = 50%
At second half life = 50%/2 = 25%
At third half life = 25%/2 = 12.5%
It means three half lives would passed.
Answer:
The density increases.
Explanation:
As you go deeper in depth, pressure increases. Density = mass/volume. The layers beneath us due to pressure get packed to the point of being very dense.
Answer:
<em>"cis" (Latin for Side) </em>
Answer:
Is a substance that can maintain certain range of pH
Explanation:
A buffer is mixture of two salts that are complementary, one salt is acid and another is basic, but since then share some part of their structure, if you add to this mixture another acid, the basic salt can absorb it and still maintaining the same pH. If you pour a base, the acid salt will absorb it and again the final pH will remain the same. So the buffers are used to maintain the same pH does not matter if you add small quantities of an acid or base.