Zad.1.

M_Na2SO4=142 g/mol

M_H2O=18g/mol

M_{Na2SO4·10H2O}=332g/mol

332g Na₂SO₄·10H₂O ― 100%

142g Na₂SO₄―x

X=44,1 % Na₂SO₄

332g Na₂SO₄·10H₂O ― 100%

180g H₂O―x

X=55,9% H₂O.

Zad.2.

M_FeS2=56g/mol+2·32g/mol=120 g/mol

M_S2=2·32g/mol= 64g/mol

120 g/mol―170kg

64 g/mol― x

X=90kg.

Zad.3.

NH₄NO₃― x kg

2N=45 kg

80g/mol ―x

28g/mol―45kg

X=128kg.

Zad.4.

(NH₄)₂HPO₄― 200 kg

M_(NH4)2HPO4= 2·14g/mol+9·1g/mol+1·31g/mol+4·13g/mol= 132g/mol

M_2N=2·14g/mol=28g/mol

132g/mol―200kg

28g/mol― x

X=42kg

M_P=41g/mol

132g/mol―200kg

31g/mol― x

X=47kg.

Zad.5.

m_Zn=100g

m_Cd=0,002g

m_Zn= 100g- 0,002g=99,998g

99,998g―100%

0,002g― x

X= 0,002%.

Zad.6.

[Cu₂(OH)₂]CO₃ → 2CuO+CO₂+H­₂O

55,5 malachitu=40g CuO+xCO₂+4,5g H₂O

Masa substratu=55,5g

Masa produktu=55,5g

X=55,5g - (40g+45g)= 55,5g- 44,5g=11g C0₂.

Zad.7.

2C₂H₂+5O₂→4CO₂+2H₂O

2dm³C₂H₂ ― 4 dm³ CO₂

10dm³ C₂H₂ ― x

X=20 dm³

2 dm³C₂H₂― 5 dm³O₂

10dm³ C₂H₂ ― y

Y=25 dm³.

Zad.8.

3Ag+4HNO₃→AgNO₃+NO₃+H₂O

M_Ag= 108g/mol

M_AgNO3=108+14+4·16=170g/mol

Z n=0,926mola Ag ―tyle samo moli AgNO₃

m_AgNO3=0,926mol·170g/mol= 157,5 AgNO₃.

Zad.9.

2HgO→O₂+2Hg

m_HgO=108,3g

M_HgO=200g/mol+16g/mol=217g/mol

M­_O2=2·16g/mol=32g/mol

V_O2=5,6 dm

108,3g―217g/mol

x―201g/mol

x=100,31g.

Zad.10.

2Al+3S→Al₂S₃

100g=n

M_Al2S3=2·27+3·32=150g/mol

M_S2=2·32=96g/mol

M_Al2=2·27g/mol= 54g/mol

150g/mol―100g

96g/mol―x_s

X=64g

150g/mol―100g

54g/mol―x

X=36g.

Zad.11.

Cu+2H₂SO₄→CuSO₄+SO₂+2H₂O

m_Cu=10g

V_SO2=?

$$n = \frac{\text{mcu}}{\text{Mcu}}$$

n=0,15mol

0,15mol·22,4=3,36dm³.

Zad.12.

m_rozp=500g

m_s= 50g

m_r= m_s+m_roz

$$Cp = \frac{\text{ms}}{\text{mr}} 100\%$$

$$Cp = \frac{\text{ms}}{ms + mrozp} 100\%$$

Cp= 9,09%.

Zad.13.

$$Cp = \frac{\text{ms}}{\text{mr}} 100\%$$

$$dr = \frac{\text{mr}}{\text{Vr}}$$

m_r=V_r·d_r=1000dm³·1,03kg/dm³=1030kg

1030·3/100= 30,9 kgNaCl.

Zad.14.

$$Cp = \frac{\text{ms}}{\text{mr}} 100\%$$

$$ms = \frac{Cp mr}{100\%}$$

m_s=50g Na₂CO₃

M_Na2CO3=106g/mol

M_{Na2CO3·10H2O}= 286g/mol

M_{Na2CO3·10H2O} : M_Na2CO3= 286:106=x:500

X=134,9g Na₂CO₃·10 H₂O.

Zad.15.

M_NaOH= 40g/mol

V_r=300cm³_­­=0,3 dm³

$$Cm = \frac{\text{ms}}{M \bullet Vr}$$

Cm= 1,5mol/dm³.

Zad.16.

M_FeCl3=162,5g/mol

$$Cm = \frac{n}{\text{Vr}}$$

$$Vr = \frac{\text{ms}}{M \bullet Cm}$$

Vr=2dm³.

Zad.17.

M_H2SO4=98g/mol

d_r=1,22g/cm³

$$Cm = \frac{Cp \bullet dr}{M \bullet 100\%}$$

Cm=3,73mol/dm³.

Zad.18.

$$Cp = \frac{\text{ms}}{\text{mr}} 100\%$$

$$ms = \frac{mr \bullet Cp}{100\%}$$

m_s=6g

Cp=12%

$$mr = \frac{\text{ms}}{\text{Cp}} 100\%$$

m_r=50g

m_w= 50g-20g=30g.

Zad.19.

m_s=? m₂=?

Cp=6%

$$Cp = \frac{\text{ms}}{\text{mr}} 100\%$$

$$ms = \frac{mr \bullet Cp}{100\%}$$

m_s=30g.

Zad.20.

Cm=?

$$Cm = \frac{ms \bullet d}{M \bullet mr}$$

m_s=12g

m_roz= 88g

d=1,1g/m3

Vr=99,6cm3

M_KOH=39+16+1=56g/mol

Cm=$\frac{12g \bullet 1,1g/mol}{56g/mol \bullet 100g} = 2,35 \bullet \frac{10^{- 3}\text{mol}}{\text{cm}^{3}} = 2,35\ mol/dm3$.

Zad.21.

m_r=100g

m_s=0,40g

d=1,004g/mol

M_NaOH=29+16+19=46g/mol

$$Cm = \frac{ms \bullet d}{M \bullet mr}$$

Cm=0,87·10^-4g/cm³= 0,87·10^-1g/dm³.

Zad.22.

m_r= 900g

m_s=$\frac{15}{100} \bullet 900g = 135g$

m_w= 900g·135g=765g

Zad.23.

V=500cm³

m_s=7,313g

$$Cm = \frac{\text{ms}}{M \bullet mr}$$

Cm=2,5·10^-4g/cm3=0,25g/dm³

M_NaCl=23+35,45=58,48g/cm³.

Zad.24.

Cp=?

V₁=300cm3

V₂= 150cm3

Cp₁= 20%

d=1,0576g/cm3

m_w= 150g

m_r=300cm3·1,0576g/cm3=317,28g

m_s= 20%·317,28g/cm=63,45g

Cp=13,58%.

Zad.25.

V₂= 400cm3

Cm₁=2mol/cm3

Cm₂=0,4mol/cm3

$$Cm = \frac{n}{\text{Vr}}$$

n=Cm·V_r

n=160mol

$$Vs = \frac{n}{\text{Cm}}$$

Vs=80cm3.

Zad.26.

n₁=4mol (H₂SO₄)

n₂= 4mol (H₂O)

$$n = \frac{\text{ms}}{M}$$

M_HSSO4=98g/mol

m_HSSO4=4mol·98g/mol=392g

M_H2O= 18g/mol

m_H2O=4·18=72g

$$Cp = \frac{\text{ms}}{\text{mr}} 100\%$$

Cp=84,48%.

Zad.27.

Cp=?

n₁=5mol(KOH)

n₂= 40mol(KOH)

M_KOH= 39+16+1= 56g/mol

m_KOH= 5·56=280g

M_H2O=2·1+16= 18g/mol

m_H2O=40·18=720g

$$Cp = \frac{\text{ms}}{\text{mr}} 100\%$$

Cp=28%.

Zad.28.

m_w= 105g

m_s= 15g (KNO₃)

Cp= 12,5%.

Zad.29.

Cp=94% m_r=?

Cp=15% m_r= 3kg

$$Cp = \frac{\text{ms}}{\text{mr}} 100\%$$

m_s=15%·3000g=450g

m_r= 478g.

Zad.30.

m_r=10g

Cp=30%

V_d= 250cm3

Cp=?

M_NaOH= 23+16+1= 40g/mol

$$Cm = \frac{\text{ms}}{M \bullet Vr}$$

Cm=0,3g/dm³

Zad.31.

V=75cm3

d= 0,8g/mol

m_s= 2,5g

$$V = \frac{\text{ms}}{d}$$

m_s=V·d

m_s=7,5·0,8=60g

Cp=4%.

Zad.32.

Cp=?

Cm=?

m_s=100g

d=1,162g/cm3

M_KNO3=39+14+3·16=101g/mol

$Cm = \frac{ms \bullet dr}{M \bullet mr}$= 2,78·10^-3

$$Cp = \frac{Cm \bullet M}{\text{dr}} \bullet 100\%$$

Cp= 24,16%.

Zad.33.

m_s2=?

m_r=100g

Cp₁=10%

m_s= m_r·Cp= 100g·10%= 10g

Cp₂= 20%

$$Cp = \frac{m_{s1} + m_{s2}}{m1 + m_{s2}}$$

Cp(m₁+m_s2)=m_s1+m_s2

Cpm­1­+Cpm_s2=m_s1+m_s2

$ms1 = \frac{Cp \bullet mr - ms2}{1 - Cp} = 12,5g$.

Zad.34.

Cp=? Cm=?

M_HCl= 36,45g/mol

V_s=67,5dm³

m_w= 440 g

dr=1,1g/cm³

d_w= 1g/cm3

V_w= 440·10^-3dm³

V_r=67,5+440·10^-3= 67,94dm³

m_r= 507,5 ·1,1=558,25

m_s= 558,25-440=11,825.

Zad. 35.

m_w=999g

m_s=1g

m_r=1000g

d_r=1g/m3

Cp=54%

m_s1= 54%·1g=0,54g

$$Cp = \frac{0,54g}{1000g} \bullet 100\% = 0,054\%$$

$$Cm = \frac{Cp \bullet dr}{M 100\%}$$

M= 2·1g/mol+32g/mol+4·16g/mol=98g/mol

$$Cm = \frac{0,054 \bullet 1}{98 100\%} = 5,51 \frac{10^{- 6}\text{mol}}{cm3}.$$

Zad.36.

CH₃COOH↔H⁺+CH₃COO^-

C_H+=C_CH3COO-=α·c= 0,019·0,05mol/dm3=0,00095mol/dm3=9,5·10^-4mol/dm3

C_CH3COOH=(1-α)c=(1-0,019)·0,05mol/dm3=0,049mol/dm3

$$K_{d} = \frac{C_{H +} \bullet C_{CH3C00 -}}{C_{CH3COOH}} = \ \frac{{(0,00095)}^{2}}{0,049} = 1,84 \bullet 10^{- 5}$$

$K_{d} = \frac{\alpha^{2} \bullet c}{1 - \alpha} = \ \frac{{(0,019)}^{2} \bullet 0,5}{1 - 0,019} = 1,84 \bullet 10^{- 5}$.

Zad.37.

H₂SO₄↔2H⁺+SO₄^2-

[H⁺]=2·0,0001= 2·10^-4 mol/dm3

pH=-log[H⁺]=-log(2·10^-4)= 3,7.

Zad.38.

Ca(OH)₂↔Ca²⁺+2OH^-

1m3=1000dm3
[OH^-]= 2·0,0002=4·10^-4mol/dm3

pH+pOH= 14

pOH=-log[OH^-]=-log(4·10^-4)= 3,4

pH= 14-3,4= 10,6.

Zad.39.

pH=? C₁=?

α=3%

C=0,02

$$C_{1} = \frac{\alpha \bullet C}{100\%} = 0,006$$

pH=-log0,006=1,22

pOH= 14-1,22= 12,78.