B
Explanation:
I rember when I learned this in 3rd grade
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.
It is a mixture
Explanation:
Food coloring is able to separate into different dyes because it just a simple mixture of different color pigments.
Under a chromatogram the different colors will migrate relatively over an absorbent.
A mixture is an impure substance with the following properties:
- composition is indefinite as they are made up of two or more elements or compounds in any proportion by mass.
- They are able to retain their identities i.e physical properties are maintained.
- Their constituents reacts differently to changed conditions.
- They can easily be separated into constituent by physical methods.
learn more:
Heterogeneous mixtures brainly.com/question/1446244
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Answer:
pH before addition of KOH = 4.03
pH after addition of 25 ml KOH = 7.40
pH after addition of 30 ml KOH = 7.57
pH after addition of 40 ml KOH = 8.00
pH after addition of 50 ml KOH = 10.22
pH after addition 0f 60 ml KOH = 12.3
Explanation:
pH of each case in the titration given below
(6) After addition of 60 ml KOH
Since addition of 10 ml extra KOH is added after netralisation point.
Concentration of solution after addition 60 ml KOH is calculated by
M₁V₁ = M₂V₂
or, 0.23 x 10 = (50 + 60)ml x M₂
or M₂ = 0.03 Molar
so, concentration of KOH = 0.03 molar
[OH⁻] = 0.03 molar
pOH = 0.657
pH = 14 - 0.657 = 13.34
