The physical letters of the third year of junior high represent and the formulas of chemistry and th

The students in front of me are very specific, and I'm embarrassed to say anything more, so you can learn more according to theirs and combine with textbooks. Good luck with your learning and progress.

It seems like it's just a physical property -- density calculations, right? The essence is m v, that is, to find density, m represents mass, v stands for volume.

m is the mass, v is the volume, m is the density, and the ratio v is the density.

Dear, do you want to express the reaction process in chemical formulas, that is, write chemical equations, please explain, or do you want any other chemistry?

Knowledge, not too understood.

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Chemistry is what structural chemistry should be.

Let the coefficients of C3H3N, C4H6, and C8H8 be x, y, and z when the CAHBNC coefficient is 1

3x+4y+8z=a

3x+6y+8z=b

x=cy=（b-a）/2

z=（3a-2b-3c）/8

Round, multiply by 8

8c c3h3n + 4（b-a）c4h6 +（3a-2b-3c）c8h8 → 8cahbnc

Let x y z be its coefficient, then there is:

For c, there is: 3x+4y+8z=a

Similarly: 3x+6y+8z=b

x=c is solved: x=c y=(b-a) 2 z=(3a-2b-3c) 8

x：y=2c：(b-a)

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The valency can only be in terms of elements, not in terms of reactants, the valency of H and O must still be so much, as for the relative molecular mass of 5H2O, it must be multiplied by 5, hope, you can ask, I hope it will help you.

Chemical Formula Relative Molecular Mass Mass Ratio of Each Element Mass Fraction of an Element.

h2o 18 1:9 o%=[ m（o）/m（h2o）]*100%=(16/18)*100%=

co2 44 3：8 o%=【m（o）/m（co2）】*100%=(16*2/44)*100=

naoh 40 23:16:1 o%=【m（o）/m（naoh）】*100%=(16/44)*100%=40%

caco3 100 10:3:12 ca%=m（ca）/m（caco3）*100%=(40/100)*100%=40%

ca(oh)2 74 20:16:1 ca%=m（ca）/m（ca(oh)2）*100%=(40/74)*100%=

2h2o 36 1:9 o%=[ m（o）/m（h2o）]*100%=(2*16/36)*100%=

Hope it works for you.

I'll give you a sample: Formula: Relative atomic Mass of O Number of Atoms of O Relative Molecular Mass of H2O 100% Process: 16 1 18 Result: 89%.