mNaOH=23u+16u+1u=40 u
23u---x%
40u---100%
x=57,5%Na
16u---x%
40u---100%
x=40%O
100%-(57,5%+40%)=2,5%H
mCa(OH)2=40u+2*16u+2*1u=74u
40u---x%
74u---100%
x=54,05%Ca
32u---x%
74u---100%
x=43,24%O
100%-(54,05%+43,24%)=2,71%H
mAl(OH)3=27u+3*16u+3*1u=78u
27u---x%
78u---100%
x=34,62%Al
48u---x%
78u---100%
x=61,54%O
100%-(34,62%+61,54%)=3,84%H
mMg(OH)2=24u+2*16u+2*1u=58u
24u---x%
58u---100%
x=41,38%Mg
32u---x%
58u---100%
x=55,17%O
100%-(41,38%+55,17%)=3,45%H