You have a stock solution of 15.6 m nh3. how many milliliters of this solution should you dilute to make 1450 ml of 0.210 m nh3? if you take a 15.0-ml portion of the stock solution and dilute it to a total volume of 0.600 l , what will be the concentration of the final solution?

For 1: 19.52mL of the stock solution must be taken.

For 2: The concentration of the final solution will be 0.39M

Explanation:

To calculate the volume or molarity of the solution, we use the equation:

where, are the molarity and volume of one solution

are the molarity and volume of another solution

= Molarity of the stock solution = 15.6M

= Volume of the stock solution = ? mL

= Molarity of the diluted solution = 0.210M

= Volume of the diluted solution = 1450 mL

Putting values in above equation, we get:

= Molarity of the stock solution = 15.6M

= Volume of the stock solution = 15 mL

= Molarity of the diluted solution = ? M

= Volume of the diluted solution = 0.600L = 600mL    (Conversion factor: 1L = 1000mL)

Putting values in above equation, we get:

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.