Answer:
13.301
Explanation:
To calculate the pH of the solution, we must obtain the pOH of the solution as illustrated below:
The dissociation equation is given below
Ba(OH)2 <==> Ba^2+ + 2OH^-
Since Ba(OH)2 dissociate to produce 2moles of OH^-, the concentration of OH^- = 2x0.1 = 0.2M
pOH = - Log[OH^-]
pOH = - Log 0.2
pOH = 0.699
But
pH + pOH = 14
pH = 14 — pOH
pH = 14 — 0.699
pH = 13.301
1/8=(1/2)^3 and the half life of radon is 3.8days
Half life is the time it takes for half of any amount of a radioactive substance to decay into something else.
Therefore for a sample of radon to decay to 1/8 of its original amount, it would take 3 x 3.8days=11.4 days
Explanation:
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We can use the dilution formula to find the volume of the diluted solution to be prepared
c1v1 = c2v2
Where c1 is concentration and v1 is volume of the concentrated solution
And c2 is concentration and v2 is volume of the diluted solution to be prepared
Substituting the values in the equation
15 M x 25 mL = 3 M x v2
v2 = 125 mL
The 25 mL concentrated solution should be diluted with distilled water upto 125 mL to make a 3 M solution