Answer:
the time required for one half of a sample of a radioisotope to decay
<u>Answer:</u> The volume of concentrated solution required is 42 mL
<u>Explanation:</u>
To calculate the molarity of the diluted solution, we use the equation:

where,
are the molarity and volume of the concentrated solution
are the molarity and volume of diluted solution
We are given:

Putting values in above equation, we get:

Hence, the volume of concentrated solution required is 42 mL
Zinc and Lead (II) nitrate react to form Zinc Nitrate and Lead.
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