Calculate the molarity of a solution containing 25.0 moles of ethanol (C₂H₅OH) in enough water to make 3.5 liters of solution?

7.14mol/dm3

Explanation:

Molarity is calculated by dividing the amount of a substance in volume of the solution.

i.e Molarity = (Amount in moles/volume in liters or dm3)

Given that:

Amount of moles = 25.0 moles

Volume = 3.5 liters of solution

Recall that 1 liter = 1dm3

so, 3.5 liters = 3.5dm3

Molarity = (25.0moles/3.5dm3)

= 7.14mol/dm3

Thus, the molarity of the solution is 7.14mol/dm3

It will take 140.76 seconds to swim 0.150 miles.

Explanation:

Distance covered by man by swimming for t time= d

d = 1500.0 miles

t = 14 minutes + 34.56 seconds

1 min = 60 seconds

t = 14 × 60 seconds + 34.56 seconds = 874.56 seconds

Speed of the man while swimming = S =

If the man swims 0.150 miles with the same speed ,then the time taken by him be T.

0.150 miles = 0.150 × 1609.34 m = 241.401 m

(1 mile= 1609.34 meters)

T = 140.76 seconds

It will take 140.76 seconds to swim 0.150 miles.