Predict whether the following pairs of solute and solvent will result in a solution that completely dissolves.
1. Sodium chloride and water
2. Sodium benzoate and water
3. Sodium benzoate and 1M HCl
4. Benzoic acid and 1M NaOH
As written this question can't be answered. How much solute in how much solvent?
1. Yes, NaCl is soluble in water in general.
2. Yes, sodium benzoate is generally soluble in water. It's a salt.
3. Sodium benzoate and 1M HCl not very soluble because the product is benzoic acid which is not very soluble.
4. Benzoic acid + NaOH is soluble generally because the produce is sodium benzoate, a salt.
1. Sodium chloride and water: Yes, sodium chloride will completely dissolve in water, resulting in a solution.
2. Sodium benzoate and water: Yes, sodium benzoate will also completely dissolve in water.
3. Sodium benzoate and 1M HCl: No, sodium benzoate is not likely to dissolve completely in 1M hydrochloric acid (HCl). It may react with the acid to form a new compound or undergo a limited degree of dissolution.
4. Benzoic acid and 1M NaOH: Yes, benzoic acid will dissolve in 1M sodium hydroxide (NaOH), resulting in a solution.
To predict whether a solute will completely dissolve in a solvent, we can consider the principle "like dissolves like". This means that substances with similar polarities are more likely to dissolve in each other.
1. Sodium chloride and water:
Sodium chloride is a polar solute, and water is a polar solvent. Both sodium chloride and water have charged particles (ions) that can interact with each other through ion-dipole forces. Therefore, sodium chloride and water will result in a solution that completely dissolves.
2. Sodium benzoate and water:
Sodium benzoate is also a polar solute, and water is a polar solvent. Similar to the previous case, sodium benzoate and water are likely to interact through ion-dipole forces. Hence, sodium benzoate should completely dissolve in water.
3. Sodium benzoate and 1M HCl:
Hydrochloric acid (HCl) is a strong acid, which means it completely dissociates into H+ ions and Cl- ions in water. Sodium benzoate is the sodium salt of benzoic acid and has the formula C7H5NaO2. When sodium benzoate is added to a solution of HCl, the H+ ions from HCl can potentially react with the sodium benzoate. This reaction would result in the formation of benzoic acid, which is a weak acid. As a result, sodium benzoate may not completely dissolve in 1M HCl, as it could react to form a new compound.
4. Benzoic acid and 1M NaOH:
Benzoic acid is a weak acid that partially dissociates in water, meaning it does not completely separate into H+ ions and the benzoate ion (C7H5O2-). Sodium hydroxide (NaOH) is a strong base that completely dissociates into Na+ ions and OH- ions in water. When benzoic acid is added to a solution of NaOH, the OH- ions from NaOH can react with the H+ ions from benzoic acid, forming water and the benzoate ion. This reaction allows benzoic acid to dissolve more completely in the presence of NaOH. Therefore, benzoic acid should dissolve more completely in 1M NaOH compared to being in water alone.