Question

Які із зазначених нижче пар йонів не можуть одночасно перебувати в розчині? а) Ca2+ і СO32─; б)Na+ і Cl─; в) Al3+ і ОН─; г) Fe2+ і NО3─ Допоможіть будь-ласка дуже треба!!

Answer 1

Ответ:

Правильна відповідь а) та в)

Объяснение:

Якщо подивитися в таблицю розчинністі, то сполуки з йоннів а) Ca2+ i CO32-; в) Al3+ i OH-; є нерозчинні

Answer 2

The ions that cannot coexist in a solution are:

а) Ca2+ and CO32─ б) Na+ and Cl─ в) Al3+ and OH─ г) Fe2+ and NO3─

These pairs of ions cannot coexist in a solution due to their opposite charges. When ions with opposite charges come into contact in a solution, they tend to form ionic compounds through a process called precipitation. Precipitation occurs when the attractive forces between the ions in the compound are stronger than the attractive forces between the ions and the surrounding water molecules.

Let's examine each pair of ions in more detail:

а) Ca2+ and CO32─: Calcium ions (Ca2+) have a positive charge, while carbonate ions (CO32─) have a negative charge. These ions cannot coexist in a solution because they will form calcium carbonate (CaCO3), which is insoluble and will precipitate out of the solution.

б) Na+ and Cl─: Sodium ions (Na+) have a positive charge, while chloride ions (Cl─) have a negative charge. These ions can coexist in a solution because sodium chloride (NaCl) is a soluble compound and will remain dissolved in the solution.

в) Al3+ and OH─: Aluminum ions (Al3+) have a positive charge, while hydroxide ions (OH─) have a negative charge. These ions cannot coexist in a solution because they will form aluminum hydroxide (Al(OH)3), which is insoluble and will precipitate out of the solution.

г) Fe2+ and NO3─: Iron(II) ions (Fe2+) have a positive charge, while nitrate ions (NO3─) have a negative charge. These ions can coexist in a solution because iron(II) nitrate (Fe(NO3)2) is a soluble compound and will remain dissolved in the solution.

To summarize, the pairs of ions that cannot coexist in a solution are: - Ca2+ and CO32─ - Al3+ and OH─

Please let me know if you need any further clarification or assistance!