A precipitation reaction is a type of chemical reaction where two soluble salts in aqueous solution react to form one or more insoluble products, known as precipitates. To determine if the given equations represent precipitation reactions, we need to check if any of the products are insoluble in water.
Let's analyze each of the given equations:
1. [tex]\( Na _2 S+ FeBr _2 \rightarrow 2 NaBr + FeS \)[/tex]
- Sodium bromide ([tex]\( NaBr \)[/tex]) is soluble in water.
- Iron(II) sulfide ([tex]\( FeS \)[/tex]) is insoluble in water.
This reaction is a precipitation reaction.
2. [tex]\( MgSO _4+ CaCl _2 \rightarrow MgCl _2+ CaSO _4 \)[/tex]
- Magnesium chloride ([tex]\( MgCl _2 \)[/tex]) is soluble in water.
- Calcium sulfate ([tex]\( CaSO _4 \)[/tex]) is slightly soluble in water but generally considered insoluble.
This reaction is a precipitation reaction.
3. [tex]\( LiOH + NH _4 I \rightarrow LiI + NH _4 OH \)[/tex]
- Lithium iodide ([tex]\( LiI \)[/tex]) is soluble in water.
- Ammonium hydroxide ([tex]\( NH _4 OH \)[/tex]) is soluble in water as it is a weak base that forms in solution.
This reaction is not a precipitation reaction.
4. [tex]\( 2 NaCl + K _2 S \rightarrow Na _2 S + 2 KCl \)[/tex]
- Sodium sulfide ([tex]\( Na _2 S \)[/tex]) is soluble in water.
- Potassium chloride ([tex]\( KCl \)[/tex]) is soluble in water.
This reaction is not a precipitation reaction.
5. [tex]\( AgNO _3+ NaCl \rightarrow AgCl + NaNO _3 \)[/tex]
- Silver chloride ([tex]\( AgCl \)[/tex]) is insoluble in water.
- Sodium nitrate ([tex]\( NaNO _3 \)[/tex]) is soluble in water.
This reaction is a precipitation reaction.
Therefore, the correct answers (equations that represent precipitation reactions) are:
- [tex]\( Na _2 S+ FeBr _2 \rightarrow 2 NaBr + FeS \)[/tex]
- [tex]\( MgSO _4+ CaCl _2 \rightarrow MgCl _2+ CaSO _4 \)[/tex]
- [tex]\( AgNO _3+ NaCl \rightarrow AgCl + NaNO _3 \)[/tex]
These are the correct precipitation reactions from the given list.
