Arrange each group of compounds/ions in order of increasing pH.
1. Li2CO3 , OH^- , NH4Br , NaCl
2. CH4 , HBr , H2O , F^-
Lastly, I'd like to check if my answers for the following three questions were listed correctly in order of pH levels increasing.
3. HBr, HF, H2O, CH4
4. CH3NH3Cl, KBr, Na2SO3, Ba(OH)2
5. HI, HCl, HS, SiH4
3,4,5 look ok. What's your trouble with the others?
I wanted to know if 1 and 2 were fine, like if it were correct.
Actually, #1 and 2 are to be answered but if I were to take a stab at it would the correct order of increasing pH be
1. Li2CO3, NaCl, NH4Br , OH^-
2. HBr , HF, H2O , CH4
To arrange the compounds/ions in order of increasing pH, we need to determine the acidity or basicity of each compound. pH is a measure of the concentration of hydrogen ions (H+) in a solution, so compounds that release more H+ ions are more acidic and have a lower pH, while compounds that release fewer H+ ions or produce OH- ions are more basic and have a higher pH.
Let's analyze each group of compounds/ions individually:
1. Li2CO3, OH-, NH4Br, NaCl:
To determine the pH, we can consider how each compound reacts in water.
- Li2CO3: Lithium carbonate is a salt formed by a strong base (LiOH) and a weak acid (H2CO3). It dissociates completely and does not affect pH.
- OH-: This is the hydroxide ion, which is a strong base and increases the pH.
- NH4Br: Ammonium bromide is a salt formed by a weak base (NH3) and a strong acid (HBr). It slightly acidifies the solution and decreases the pH.
- NaCl: Sodium chloride is a neutral salt and does not affect the pH.
Considering this, the order of increasing pH for this group is: NH4Br < NaCl < Li2CO3 < OH-.
2. CH4, HBr, H2O, F-:
In this group, we can consider the acidity or basicity of each compound.
- CH4: Methane is a neutral compound and does not affect the pH.
- HBr: Hydrogen bromide is a strong acid and decreases the pH.
- H2O: Water is a neutral compound and does not impact the pH.
- F-: This is the fluoride ion, which is a weak base and slightly increases the pH.
Based on this information, the order of increasing pH for this group is: HBr < CH4 < H2O < F-.
Now let's check your answers for the remaining questions:
3. HBr, HF, H2O, CH4:
Based on the acidity and basicity of each compound:
- HBr: Strong acid (decreases pH).
- HF: Weak acid (slightly decreases pH).
- H2O: Neutral (does not affect pH).
- CH4: Neutral (does not affect pH).
The correct order of increasing pH should be: HBr < HF < CH4 < H2O.
4. CH3NH3Cl, KBr, Na2SO3, Ba(OH)2:
Considering the acidity or basicity of each compound:
- CH3NH3Cl: Ammonium chloride is a salt formed by a weak base (NH3) and a strong acid (HCl), slightly decreases the pH.
- KBr: Potassium bromide is a neutral salt and does not impact pH.
- Na2SO3: Sodium sulfite is a weak base and increases the pH slightly.
- Ba(OH)2: Barium hydroxide is a strong base, significantly increasing the pH.
The correct order of increasing pH should be: CH3NH3Cl < KBr < Na2SO3 < Ba(OH)2.
5. HI, HCl, HS, SiH4:
Considering the acidity or basicity of each compound:
- HI: Hydrogen iodide is a strong acid and decreases the pH.
- HCl: Hydrogen chloride is a strong acid and decreases the pH.
- HS: Hydrosulfide ion is a weak acid (slightly decreases pH).
- SiH4: Silane is a neutral compound and does not affect pH.
The correct order of increasing pH should be: HI < HCl < HS < SiH4.
I hope this helps!