Quyidagi atomlarning absolyut massalari berilgan. Ularning nisbiy atom massalarini toping: tcmir— 93,13-10"27kg; vodorod— 6710""7kg: uran —396,67-10": 7kg. 20- bet

7 sinf kimyo fanidan mavzuli masalalarning yechimlar to`plami .

I-BOB 4& Atomlarning olchami nisbiy atom massa.

1. 
   Quyidagi atomlarning absolyut massalari berilgan. Ularning nisbiy atom massalarini toping: 1) tcmir— 93,13-10"²⁷kg; 2) vodorod— 1.6710""⁷kg: 3)uran —396,67-10"^:7kg. 20- bet
   

Ar_Fe=93,13.10²⁷ =56.10

1.66.10^27
Ar _H=1.67*10²⁷ =1

1.66.10²⁷

_Ar

^Ar _H=396.67*10²⁷ =238.95

1.66.10²⁷

I-BOB 10& Molekulalrning olchami nisbiyva mol massa.

1. H₂S0₄, A1₂0₃, Ca₃(P0₄)₂ moddalarining nisbiy molekular massalarini hisoblang.

Mr_H2SO4=2+32+(16*4)=98

Mr_AL2O3=(27*2)+(16*3)=54+48=102

Mr_Ca3PO4=3*40+31+(16*4)=120+31+64=215

5. 
   0.5mol kislarod va vodorodning massalarini aniqlang.
   

1mol O₂-----32g 1mol H₂----2g

0.5mol-----x=16g 0.5mol-----x=1g

5. 
   18g suvda nechta molekula bor.
   

H₂O Mr=1*2+16=18 18g suv----1mol------6.02*10²³ta atom bor.

I-BOB 11-& Moddalarning xossalari.

5. SO₃ ning molekular massasini va 16 g SO₃ dagi modda miqdorini. mole­kulalar sonini nisoblang.

1) Mr_SO3=32+(16*3)=48+32=80

2) 16_g SO3-------X=0,2mol

80_g SO3--------1mol

3) 16_g SO3------X=30,1*10²³

80_g SO3--------6,02*10²³

_I-BOB 13& Tarkibning doimiylik qonuni

2. 
   ^{FeO va Fe2O3 kar tarkibidagi elementlarning massa ulushlarini aniqlang . Temirning massa ulushi qaysi birikmada ko`p?}
   

1. 
   ^MrFeO=72
   

^{m(Fe)=56/72=0,77 m(O)=16/72=0,23}

2. 
   ^MrFe2O3=160
   
3. 
   ^{m(Fe)=112/160=0,7 m(O)=48/160=0.3}
   

^{I-BOB 14& Massaning saqlanish qonuni.}

2. 50 g ohaktosh —CaCO3; parchalanganda 28 g qattiq qoldiq — CaO olindi. 22 g massa qayerga yo’qoldi? Bu hodisani izohlang.

CaCO3= CaO+CO2