Question

Cine poate rezolva,,ms

Answer 1

1.

d(aer) = miu(Hg vapori) / miu(aer)

d(aer) = 6,92 => miu(Hg) = d(aer)xmiu(aer)

= 200 g Hg adica 1 mol de Hg

2.

c% = mdx100/ms = 26%

(ro) p = ms/Vs = 1,24 g/ml => ms = 5000 x 1,24 = 6200 g sol KOH

=> md = msxc/100 = 6200x26/100 = 1612 g KOH

3.

Zn(NO3)2 + NaOH => NaNO3 + Zn(OH)2

Zn(+2) + 2(NO3)(-) => Na(+) + NO3(-) + Zn(+2) + 2HO(-)

Zn(OH)2 + K2O => K2ZnO2 + H2O

Zn(+2) + 2HO(-) + 2K(+) + O(-2) => 2K(+) + (ZnO2)(-2) + H(+) + HO(-)

4.

vezi teoria predata........

5.

α = gradul de dilutie ≅ conc.% = 4,2%

stim ca Cn = md/EgxVs

Eg = echivalentul gram = M.molec. / nr. HO- = 35/1 = 35 g

=> Vs = md/CnxEg

Vs = md/M.molec.xCm

=> md/M.molec.xCm = md/EgxCn

=> 1/Cm = 1/Cn => Cm = Cn = 0,01 M

pOH = - lg[HO-] = -lg(10la-2) = -(-2) = 2

=> pH + pOH = 14 => pH = 14 - 2 = 12

6.

2CH4 --1500oC--> C2H2 + 3H2

HC≡CH + H2 --Ni--> H2C=CH2

H2C=CH2 + H-OH --H+--> H3C-CH2-OH

2H3C-CH2-OH --ZnO/450oC--> H2C=CH-HC=CH2