I am sure I am doing this Acid/Base problem wrong

In summary, the conversation discusses how to find the pH of a solution made from a given amount of H2SO4 and Al(OH)3. The participants mention using RICE to solve the problem, but the person speaking is unsure of how to use it. They suggest first updating the concentrations of the acid and base in the solution, then calculating the remaining amount of acid or base after the neutralization reaction. However, there is disagreement about whether to treat the Al(OH)3 as completely dissociated or consider its solubility product. Ultimately, the difficulty of the problem is acknowledged.
  • #1
Renee Crosby
1
0
What is the pH of a solution made from 34.6 ml if 3.45*10^-4 M of H2SO4 added to 41.7 ml of 4.56*10^-4 M of Al(OH)3?

I know how to find H+ and OH- and pH I also know how to use x mol / L, but I cannot get them to click together. Everyone keeps telling me to use RICE but my professor never explained what this was to us.

I keep trying different ways to start this problem and they all look wrong. This is the only problem that I don't even know how to put together from the start.
 
Physics news on Phys.org
  • #2
First update the concentrations of acid and base in the total solution of 76,3ml
Then write down the chemical neutralization reaction between the acid and the base.
Then calculate how much acid (or it might be base) that will be left. If it is acid that will be left then you can find [H+]* (and [OH-] will follow)
If it is base that will be left then you can find [OH-] and then [H+].

* have in mind that extra water will be produced from the neutralization reaction so you should update the concentration of the acid left (or base left).
 
  • #3
What if you were told to start it just as a limiting reagent problem?

But I don't like this question. Unless you are expected to ignore the Al(OH)3 insolubility and to treat the solution as if Al(OH)3 was completely dissociated (which is not true) finding the answer is pretty tricky.
 
  • #4
Borek said:
What if you were told to start it just as a limiting reagent problem?

But I don't like this question. Unless you are expected to ignore the Al(OH)3 insolubility and to treat the solution as if Al(OH)3 was completely dissociated (which is not true) finding the answer is pretty tricky.
Can we say impossible to solve? The solubility product of Al(OH)3 is absolutely essential.
 

FAQ: I am sure I am doing this Acid/Base problem wrong

1. Why am I getting different answers when I try to solve this Acid/Base problem?

There could be a few reasons for this. One possibility is that you are using different values for the same variables. Make sure you are using the correct values in all of your calculations. Another possibility is that you are using different equations or methods to solve the problem. Check your work to ensure consistency. Finally, it is possible that you made a mistake in your calculations. Double check your work and try to identify any errors.

2. How can I tell if I am using the right Acid/Base equation for this problem?

The best way to determine which equation to use is to identify the type of Acid/Base reaction you are working with. There are several types of Acid/Base reactions, including neutralization, acid-base titration, and buffer solutions. Once you know the type of reaction, you can select the appropriate equation to solve the problem.

3. What is the best approach for solving an Acid/Base problem?

The best approach for solving an Acid/Base problem is to first identify the type of reaction you are working with. Then, gather all of the necessary information, such as the concentrations and volumes of the acid and base solutions. Next, use the appropriate equation to calculate the unknown variable. Finally, double check your work and make sure your answer makes sense based on the given information.

4. What should I do if I am still unsure about my answer after solving an Acid/Base problem?

If you are unsure about your answer, it is always a good idea to double check your work and make sure you used the correct equation and values. You can also consult a classmate or your instructor for assistance. Additionally, you can look for similar examples or practice problems to compare your answer to and gain a better understanding of the concept.

5. How important is it to understand Acid/Base problems in the field of science?

Acid/Base problems are crucial to understand in the field of science, particularly in chemistry and biology. These concepts are fundamental to understanding how different substances interact with each other, and are also important for many practical applications, such as pharmaceuticals, agriculture, and environmental science. Additionally, understanding Acid/Base reactions can help you to better comprehend more complex chemical reactions and processes.

Similar threads

Back
Top