Nizomiy nomidagi tdpu tabiiy fanlar fakulteti

3. 51 gr ammiakdagi (NH3) modda miqdorini aniqlang.
Yechish: (NH3)=51/173 J:3 mol.


4. 0.4 mol miqdoridagi mis kuporosi (CuSO₄x5H₂O) massasini hisoblang.
Yechish: (CuSx5H2O)=160gr.
1molda------------160gr
0.4------------------X gr.
X=100 gr J:100gr.


5. 2 mol miqdordagi malaxit (Cu(OH)₂xCuCO₃) massasini hisoblang.
Yechish: (Cu(OH)xCuCO₃)=222gr.
1molda------------------------222g
2molda------------------------X gr.
X=444 gr. J:444 gr.
6. 0.3 mol miqdoridagi so’ndirilmagan ohak (CaO) massasini hisoblang.
Yechish: (CaO)=56gr
1molda --------------56 gr
0.3 molda-----------X gr.
X=16.8 gr J: 16.8 gr
7. 96.6 gr glauber tuzi (Na₂SO₄x10H₂O) dagi modda miqdorini aniqlang.
Yechish: Na₂SO₄x10H₂O=322gr.
322gr--------------1 mol
96.6 gr------------x mol.
X=0.3 mol. J: 0.3 mol.
8. 0.25 mol miqdordagi dolomit (CaCO₃xMgCO₃) massasini hisoblang.
Yechish: (CaCO3xMgCO3)=184gr.
184gr---------------1 mol
x-------------------0.25mol x=46 gr J:46 gr.
9. 0.3 mol miqdoridagi so’ndirilgan ohak (Ca(OH)₂) massasini hisoblang.
Yechish: (CA(OH)₂)=74gr.
74gr----------------1mol
x--------------------0.3 mol
x=22.2gr. J: 22.2gr.
10. 12 gr marmardagi (CaCO₃) modda miqdorini naniqlang.
Yechish:CaCO₃=100gr.
100gr-------------1mol x=0.12 mol. J:0.12 mol.
12 gr --------------xmol.
Mol. Molyar massa masalalar yechish.
1-masala. 176 g massali oltingugurtda atom holidagi oltingugurt moddasida qancha miqdorda borligini aniqlang.
Yechish: Oltingugurtning nisbiy atom massasi, A_r (S)=32². Atomar oltingugurtning molyar massasi 32g/molga teng. Demak, 176 g da quyidagi atomar oltingugurt bo‘ladi.
176:32 mol=5,5 mol.
2-masala. 40 g CaCO₃ da necha mol kalsiy karbonat borligini hisoblab topish.
¹ Bu qiymatdan agar bosim Pa da, hajm esa m³ da yoki tegishlicha k Pa va / da o‘lchangan bo‘lsagina foydalaniladi.
² Bu yerda va bundan keyin masalalar yechishda maxsus aytib o‘tilmagan bo‘lsa nisbiy atom massalarining yaxlitlangan qiymatlaridan foydalaniladi.
Yechish: CaCO₃ ning nisbiy molekular massasi Mr (CaCO₃)=40+12+3x16=100, ya‘ni kalsiy karbonatning molyar masssi 100 g\molni tashkil etadi. Demak, 40 g da quyidagi miqdorda CaCO₃ bo‘ladi:
40:100mol=0,4 mol.
3-masala. 15 mol kaliy nitratning massasini aniqlang.
Yechish. Kaliy nitratning molyar massasi 101 g/molga teng. (1.1) formulaga muvofiq 15 mol KNO₃ ning massasi 15x101 g=1515 g bo‘ladi.
4-masala. Kumushning nisbiy atom massasi 108 g ga teng. Bir atom kumushning grammlar hisobidagi massasini aniqlang.
Yechish: Kumush atomlarining molyar massasi son jihatdan nisbiy atom massasiga teng bo‘lganligi sababli u 108 g/molga teng. 1 mol kumushda 6,02x10^-23 atom borligini bilgan holfda bir atomning massasini topamiz:
108:6,02x10^-23 mol =1,79x10^-24 g.
5-masala. 6,8 g vodorod sulfidda nechta molekulabor? Bitta H₂S molekulasining massasini hisoblaymiz.
Yechish: H₂S ning molyar massasi 34 g/molga teng. 6,8 g dagi vodorod sulfidning mollar sonini aniqlaymiz:
6,8:34 mol =0,2 mol
Vodorod sulfid bitta molekulasining massasini aniqlaymiz:34:6,02x10²³ g =5,65x10^-23 g.