A stock solution of HNO3 is prepared and found to contain 13.1 M of HNO3. If 25.0 mL of the stock solution is diluted to a final volume of 0.500 L, the concentration of the diluted solution is M.

The diluted solution is 0.65 M

Explanation:

Dilution formula to solve the problem is:

M concentrated . V concentrated = M Diluted . V diluted

We can also make a rule of three though.

In 1000 mL of concentrated solution, we have 13.1 moles of  HNO₃

So in 25 mL we have (25 . 13.1 ) / 1000 = 0.327 moles of HNO₃

This moles are also in 0.500 L of diluted solution, the new molarity will be:

0.327 mol / 0.5L = 0.65 M

Molarity of diluted solution must be always lower than concentrated solution, otherwise the excersise is wrong.

If we replace in the formula

13.1 M . 25 mL = 500 mL . M diluted

M diluted = 13.1 m . 25 mL / 500 mL = 0.65 M

explanation:

metals have excess of electrons whereas non-metals have deficiency of electrons. thus, in order to gain stability metals easily donate their electrons to the non-metals.

for example, electronic configuration of sodium is and electronic configuration of phosphorous is .

when a phosphorous atom and sodium atom combine together then sodium will donate is extra one electron to the phosphorous atom. as a result there will be formation of ionic bond between sodium and phosphorous.

the reaction will be as follows.

there, are three sodium sodium atoms and each of them will donate its one extra electron to phosphorous atom. thus, the sub-shell of phosphorous gets completely filled.  

thus, we can conclude that electrons are transferred from atoms of sodium to atoms of phosphorous. this transfer makes the sodium atoms donate one electron and the phosphorous atoms to gain one electron. as a result, the sodium and phosphorus atoms strongly attract each other.

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environmental implications of pesticides

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health implications of organics

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health implications of pesticides

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other important considerations

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