Question

Ajutor am nevoie urgent sa imi rezolvați si mie, dau 50 de puncte, va si urmăresc!! ​

Answer 1

1.

1-b

2-a

3-f

4-e

5-c

2.

a)

ms1 = 200g , c1% = 20%

ms2 = 200g , c2% = 10%

stim ca c% = mdx100/ms

=>

md1 = ms1xc1%/100

= 200x20/100 = 40 g

md2 = ms2xc2%/100

= 200x10/100 = 20 g

=> md.tot = 40+10 = 50 g

ms.tot = ms1+ms2 = 400 g

=> c%.final = ms.totx100/ms.tot

= 50x100/400 = 12,5%

b)

md = 4 g NaOH, Vs = 250 mL = 0,25 L

stim Cm = md/miuxVs, miu.NaOH = 40 g/mol

=> Cm = 4/40x0,25 = 0,4 mol/L

3.

 +5            -2      0    +2

HNO3 + H2S --> S + NO + H2O

2x    N⁺⁵_+3e-_> N⁺² reducere (ag. ox) HNO3

3x    S⁻²_-2e-_> S⁰ oxidare (ag red) H2S

2HNO3 + 3H2S --> 3S + 2NO + 4H2O