Completează rubricile din tabelul următor:
Răspunsuri la întrebare
Răspuns:
Explicație:
HCl
Vs= 2L
cm=0,1m
cm= n : Vs
n=cm . Vs
n= 0,1 moli/L . 2L=0,2 moli
m=n . M
MHCl=1+35,5=36,5------>36,5g/moli
m=0,2 moli . 36,5g/moli=7,3g HCl
m=7,3 g HCl
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KOH
n=1kmol=100moli
cm=0,5moli /L
Vs
cm= n : Vs
Vs=n :cm
Vs=1000moli : 0,5 moli / L=500 L=500dm³ [1dm³=1L ]
Vs=500L
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NaCl
m=117kg=117000g NaCl
Vs=1000L
cm
MNaCl=23 +35,5=58,5----->58,5g/moli
cm= n : Vs
n=117000g : 58,5g/moli=2000moli NaCl
cm=2000moli : 1000L=2 moli /L
cm=2
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Ca(OH)2
m=74g
Vs=1000ml = 1L
cm
M=40+ 2.16 +2=74g/moli
n=74g : 74g/moli=1mol Ca(OH)2
cm = n : Vs
cm=1mol : 1L=1mol/L
cm=1
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Al2(SO4)3
Vs=25 m l= 0,025L
cm=10
m
cm= n : Vs
n=cm . Vs
n=10moli/ L . 0,025L=0,25 moli Al2(SO4)3
M=2.27 +3.32 +12.16=342------->342g/moli
m=n .M
m=0,25moli . 342g/moli=85,5 g Al2(SO4)3
m=85,5 g
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am rezolvatacum trece tu in tabel valorile pentru fiecare , le-am subliniat