Calculate the ionic strength of the solution.
a) 100 mL of 0.8M magnesium perchlorate, Mg(ClO4)2, is added to 900 mL of 0.30M perchloric acid, HClO4. No reaction.
B)25 mL of 0.200M potassium iodide, KI, are mixed with 75 mL of 0.0300 M silver nitrate, AgNO3. Silver iodide precipitates.
For (a) you first need to determine the molarity of the resulting Mg(ClO4)2 and HClO4. Then use the ionic strength formula to determine the ionic strength. That is mu = AZ1^2 + BZ2^2 + CZ3^2where A is the Mg^+2 ion molarity and Z1^2 is the charge on the Mg^+2; B is the total molarity of the ClO4^- and Z2^2 is the charge on the ClO4^- ion; C is the molarity of the H^+ and Z3^2 is the charge on the H^+. For (b), you must first determine the reaction (a ppt of AgI will take place) and use the rxn to determine the final molarities of K^+, I^-, NO3^- and Ag^+. Then plug into the mu forumla to determine ionic strength. Please post your work if you need further assistance or if you would like us to check your answer. We need your work in order to determine the nature of your problem (but you probably won't have any trouble.) I hope this helps you get started.
I just noticed that I omitted the 1/2 on mu. It should read
nu = 1/2(AZ1^2 + BZ2^2 + CZ3^2) etc. Sorry about that.
That's mu and not nu. =)
define Physical science
Andrew:
You did the correct thing by posting a SEPARATE posting for this question. I saw this posting just by chance. I answered the later posting above. However, for definitions you can go to www.dictionary.com and look them up much faster than typing them here and waiting for a reply.
It's great to see that you've already found a solution to your problem. As for defining physical science, I'm not sure you would want my definition. I might say it's the science of "physics"al things, like not being able to find your keys when they're right in front of you. But in all seriousness, physical science is the branch of science that deals with the study of non-living systems and how they interact with each other. It includes subjects like physics, chemistry, astronomy, and geology.
To calculate the ionic strength of a solution, you need to determine the molarities of the ions present and their respective charges. Here are the steps to calculate the ionic strength for each given scenario:
a) 100 mL of 0.8M magnesium perchlorate, Mg(ClO4)2, is added to 900 mL of 0.30M perchloric acid, HClO4.
1. Calculate the molarities of Mg^2+, ClO4^-, and H+:
- Molarity of Mg^2+: 0.8 M
- Molarity of ClO4^-: 2 * 0.8 M = 1.6 M (due to the 2:1 ratio of Mg^2+ to ClO4^-)
- Molarity of H+: 0.30 M
2. Calculate the ionic strength using the ionic strength formula:
Ionic strength (mu) = 1/2(AZ1^2 + BZ2^2 + CZ3^2)
- A = Molarity of Mg^2+
- Z1^2 = Charge on Mg^2+ (2^2 = 4)
- B = Molarity of ClO4^-
- Z2^2 = Charge on ClO4^- (1^2 = 1)
- C = Molarity of H+
- Z3^2 = Charge on H+ (1^2 = 1)
Ionic strength (mu) = 1/2(0.8 M * 4 + 1.6 M * 1 + 0.30 M * 1) = 0.8 M
Therefore, the ionic strength of the solution is 0.8 M.
b) 25 mL of 0.200M potassium iodide, KI, are mixed with 75 mL of 0.0300 M silver nitrate, AgNO3.
1. Determine the reaction occurring between KI and AgNO3:
KI + AgNO3 → AgI + KNO3
Silver iodide (AgI) precipitates.
2. Calculate the molarities of the ions present after the reaction:
- Molarity of K+: 0.200 M (no change)
- Molarity of I-: 0.200 M (no change)
- Molarity of NO3-: 0.0300 M (no change)
- Molarity of Ag+: 0.025 M (0.0300 M * 0.75 due to the 1:1 ratio of Ag+ to I-)
3. Calculate the ionic strength using the ionic strength formula:
Ionic strength (mu) = 1/2(AZ1^2 + BZ2^2 + CZ3^2)
- A = Molarity of K+
- Z1^2 = Charge on K+ (1^2 = 1)
- B = Molarity of I-
- Z2^2 = Charge on I- (1^2 = 1)
- C = Molarity of NO3-
- Z3^2 = Charge on NO3- (1^2 = 1)
Ionic strength (mu) = 1/2(0.200 M * 1 + 0.200 M * 1 + 0.0300 M * 1) = 0.215 M
Therefore, the ionic strength of the solution is 0.215 M.
Please note that the calculations may vary depending on the specific properties and charges of the elements/compounds involved.
To calculate the ionic strength of the solution, we first need to determine the molarities of the ions present in the solution. Let's start with (a).
(a) 100 mL of 0.8M magnesium perchlorate, Mg(ClO4)2, is added to 900 mL of 0.30M perchloric acid, HClO4.
To find the molarity of the resulting solution of Mg(ClO4)2, we need to use the following equation:
M1V1 = M2V2
Where M1 is the initial molarity (0.8M) and V1 is the initial volume (100 mL), M2 is the final molarity we want to find, and V2 is the final volume (the sum of the initial volumes, 100 mL + 900 mL = 1000 mL = 1 L).
So, plugging in the values, we have:
(0.8M)(0.1L) = M2(1L)
0.08 = M2
So, the molarity of the resulting Mg(ClO4)2 is 0.08M.
To find the molarity of HClO4, we follow the same process:
(0.30M)(0.9L) = M2(1L)
0.27 = M2
So, the molarity of the resulting HClO4 is 0.27M.
Now that we have the molarities, we can proceed to calculate the ionic strength. The ionic strength (represented by the Greek letter μ) is given by the formula:
μ = 1/2(AZ1^2 + BZ2^2 + CZ3^2)
Where A, B, and C are the molarities of the ions in the solution, and Z1, Z2, and Z3 are the charges of the ions squared.
In this case, A is the molarity of Mg^2+, B is the molarity of ClO4^-, and C is the molarity of H^+. The charges squared (Z1^2, Z2^2, Z3^2) are 2^2, (-1)^2, and (1)^2 respectively.
Plugging in the values, we have:
μ = 1/2((0.08M)(2^2) + (0.08M)(-1)^2 + (0.27M)(1)^2)
Simplifying the equation, we get:
μ = 1/2(0.32 + 0.08 + 0.27) = 0.335
So, the ionic strength of the solution in (a) is 0.335.
For (b), you will need to go through a similar process of determining the molarities of the ions present and then using the ionic strength formula to calculate the ionic strength of the solution.