dont know why all the index numbers came above the letters in my post but they are meant to be below.(adsbygoogle = window.adsbygoogle || []).push({});

250ml of Mg(NO[tex]_{3}[/tex])[tex]_{2}[/tex] with a density of 45g/L are mixed with 75 ml Na[tex]_{3}[/tex]PO[tex]_{4}[/tex] with a density of 30g/l.

what is the mass of the product Mg[tex]_{3}[/tex](PO[tex]_{4}[/tex])[tex]_{2}[/tex]

what i did was, using the densities, found out the masses of the molecules and then using the masses found out the amount of given mol's of each.

what i get is

0.071 mol Mg(NO[tex]_{3}[/tex])[tex]_{2}[/tex]

0.0137 mol Na[tex]_{3}[/tex]PO[tex]_{4}[/tex]

giving me a ratio of about 5:1

so

5Mg(NO[tex]_{3}[/tex])[tex]_{2}[/tex]+ Na[tex]_{3}[/tex]PO[tex]_{4}[/tex] ----> Mg[tex]_{3}[/tex](PO[tex]_{4}[/tex])[tex]_{2}[/tex]

problem comes here, i need to balance the equation to continue,

but i have missing elements?? what do i do?

once i have balanced the equation i can see how many mols of Mg[tex]_{3}[/tex](PO[tex]_{4}[/tex])[tex]_{2}[/tex] i have and then i fan work out its mass.

how do i add up the missing elements?

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# Homework Help: Chemistry, equation and formula

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