1) Mr(NH3)=14+1*3=17
Mr(H3PO4)=1*3+31+16*4=98
Mr(Al(OH)3)=27+16*3+1*3=78
2)Mr(NH3)=17
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W(N)-?
W(H)-?
W(N)=14\17=0,8=80%
W(H)=1*3\17=0,2=20%
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Mr(H3PO4)=98
W(H)-?
W(P)-?
W(O)-?
W(H)=1*3\98=0,03=3%
W(P)=31\98=0,32=32%
W(O)=16*4\98=0,65=65%
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Mr(Al(OH)3)=78
W(Al)-?
W(H)-?
W(O)-?
W(Al)=27\78=0,35=35%
W(O)=16*3\78=0,61=61%
W(H)=1*3\78=0,04=4%
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