V(PH3)-?
m(PH3)/M(PH3) = V(PH3)/Vm Vm=22.4 L/mol M(PH3)=34 g/mol
V(PH3)=m(PH3)*Vm/M(PH3)= 3.6*22.4 / 34=2.37 литров
N(PH3)= (m/M)*N(A) N(A)=6.02*10^23
N(PH3)= 3.6 / 34 * 6.02*10^23 = 0.637 *10^23 молекул
Количество атомов фосфина = 4
N(PH3)=(m/M)*N(A)*n, n=4
N(PH3)=3.6/34*6.02*10^23*4=2.55*10^23 атомов
D(H2)= M(PH3) / 2= 34/2=17
D(He)=M(PH3) / 4=34/4=8.5
D(возд)=M(PH3)/29 = 34/29=1.17
ответ
2.37 л, 0.637 *10^23 молекул , 2.55*10^23 атомов , D(H2)=17 ,
D(He)=8.5 , D(возд)=1.17
2NaOH + H2SO4 = Na2SO4 + 2H2O
n(Na2SO4) = 250/142 = 1.76
n(NaOH) = 3.52
m(NaOH) = 3.52 * 40 = 140.8 г
<span>Амфотерные гидроксиды:
Zn(OH)2
</span><span>Cr(OH)3</span>
MCH3OOH=240*10/100=24 г
nCH3COOH=24/Mr(60)=0,4 моль
CH3OOH+NaOH=CH3COONa+H2O
nCH3COONa=nCH3COOH=0,4 моль
mCH3COONa=0,3*Mr(59+23=82)=32,8г. масса соли
<span>K2CR2O7+ 4H2So4+ 3Na2So3-> CR2(SO4)3+ 3NA2SO4+K2SO4+ 4H2O
2Cr(+6) +6e = 2Cr(+3) 1
S(+4) - 2e = S(+6) 3</span>