Đáp án:
2P +5/2O2 --> P2O5
0,4 0,5 0,2
sản phẩm là P2O5: đi photpho penta oxit
nP2O5=$\frac{28,4}{31.2+16.5}$=0,2
mP=0,4.31=12,4g
VO2=0,5.22,4=11,2lit
Vkk=11,2.5=56lit
Giải thích các bước giải:
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x+2/2008+x+3/2007+x+4/2006+x+2028/6=0
giải phương trình sau3x(25x+15)-35(5x+3)=0
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