Calculate the mass of strontium hydroxide required to make a 450-mL solution with a pOH of 4.00.
Step 1: Find pOH. I found that pOH is 10.
The next steps is where I'm stuck.
Step 2 :Calculate the hydroxide ion concentration. Express your answer in scientific notation.
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mol/L.
Answer:
Step 3: Calculate the concentration of strontium hydroxide. Express your answer in scientific notation.
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mol/L.
Answer:
Step 4: Determine the number of moles of Sr(OH)2(aq). Express your answer in scientific notation.
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mol.
Answer:
Step 5: Determine the mass of Sr(OH)2(s)
The pOH is 10.
To convert pOH = 10 to OH^-, it is
pOH = -log(OH^-)
10 = -log(OH^-)
-10 = log(OH^-)
Take antilog of both sides.
1 x 10^-10 = OH^-
Whoa, hold on there! Let's tackle this step by step, but first, let me crack a joke to lighten the mood:
Why did the chemist refuse to share their solutions?
Because they were always diluting the conversation!
Okay, now let's get back to business.
Step 1: You mentioned that the pOH is 10, but then you also said it's 4.00. Let's assume it's 4.00 for now, unless you're just giving me options to choose from!
Step 2: To find the hydroxide ion concentration, we need to convert pOH to OH- concentration. Remember that pOH = -log[OH-], so if pOH = 4.00, then [OH-] = 10^(-4.00). Got it?
Step 3: Now, we need to calculate the concentration of strontium hydroxide. But before that, let me add a little laughter:
Why did the acid go to the gym?
To become a buffer solution, of course!
Okay, moving on! Strontium hydroxide is a strong base, so it fully dissociates in water to give one strontium ion (Sr2+) and two hydroxide ions (OH-). The concentration of strontium hydroxide will be the same as the concentration of hydroxide ions.
Step 4: To determine the number of moles of Sr(OH)2(aq), we multiply the concentration of Sr(OH)2(aq) by the volume of the solution (in liters). But wait, before we do that, let me share another joke with you:
Why did the chemist only tell bad jokes?
Because all the good ones are argon!
Okay, back to the calculation!
Step 5: Now that you know the number of moles of Sr(OH)2(aq), you can calculate the mass of Sr(OH)2(s) by multiplying the number of moles by the molar mass of strontium hydroxide. Don't forget to include a laugh as part of your solution!
I hope this helps, and feel free to ask for more clarification if needed.
Step 2: Calculate the hydroxide ion concentration.
To calculate the hydroxide ion concentration (OH-) from the pOH value, we can use the equation:
OH- concentration = 10^(-pOH)
Let's plug in the given pOH value of 4:
OH- concentration = 10^(-4)
OH- concentration = 0.0001 mol/L
Step 3: Calculate the concentration of strontium hydroxide.
Strontium hydroxide (Sr(OH)2) ionizes in water to produce two hydroxide ions (OH-) for every one strontium ion (Sr2+). Therefore, the concentration of strontium hydroxide will be twice the hydroxide ion concentration.
Concentration of Sr(OH)2 = 2 * OH- concentration
Concentration of Sr(OH)2 = 2 * 0.0001 mol/L
Concentration of Sr(OH)2 = 0.0002 mol/L
Step 4: Determine the number of moles of Sr(OH)2(aq).
To calculate the number of moles of strontium hydroxide, we need to multiply the concentration (in mol/L) by the volume (in L) of the solution.
moles of Sr(OH)2 = concentration * volume
moles of Sr(OH)2 = 0.0002 mol/L * 0.450 L
moles of Sr(OH)2 = 0.00009 mol
Step 5: Determine the mass of Sr(OH)2(s).
The molar mass of Sr(OH)2 is the sum of the atomic masses of strontium (Sr), hydrogen (H), and oxygen (O). The atomic masses are:
Sr: 87.62 g/mol
H: 1.01 g/mol
O: 16.00 g/mol
Molar mass of Sr(OH)2 = (87.62 g/mol + 2*(1.01 g/mol) + 2*(16.00 g/mol))
Molar mass of Sr(OH)2 = 121.63 g/mol
To calculate the mass of Sr(OH)2, we multiply the number of moles by the molar mass:
mass of Sr(OH)2 = moles of Sr(OH)2 * molar mass
mass of Sr(OH)2 = 0.00009 mol * 121.63 g/mol
mass of Sr(OH)2 = 0.01095 g
Therefore, the mass of strontium hydroxide required to make a 450-mL solution with a pOH of 4.00 is approximately 0.01095 grams.
To calculate the mass of strontium hydroxide required, follow these steps:
Step 2: Calculate the hydroxide ion concentration.
To find the hydroxide ion concentration, you can use the formula: pOH = -log[OH-]. Since the pOH is given as 4.00, we can calculate the hydroxide ion concentration as follows:
OH- concentration = 10^(-pOH)
OH- concentration = 10^(-4.00)
Calculating this gives us the concentration of hydroxide ions in mol/L.
Step 3: Calculate the concentration of strontium hydroxide.
Strontium hydroxide (Sr(OH)2) dissociates in water to give two hydroxide ions (OH-) per molecule. Therefore, the concentration of strontium hydroxide would be twice the concentration of hydroxide ions calculated in Step 2.
Sr(OH)2 concentration = 2 * OH- concentration
Convert the concentration to scientific notation if necessary.
Step 4: Determine the number of moles of Sr(OH)2.
To calculate the number of moles, you can use the formula: moles = concentration * volume.
Moles of Sr(OH)2 = Sr(OH)2 concentration * volume
In this case, the volume is given as 450 mL. Convert the volume to liters if necessary.
Step 5: Determine the mass of Sr(OH)2.
To find the mass, you can use the formula: mass = moles * molar mass.
The molar mass of Sr(OH)2 can be found by adding up the atomic masses of strontium (Sr), oxygen (O), and hydrogen (H). Multiply the molar mass by the number of moles calculated in Step 4 to determine the mass of strontium hydroxide required.
Note: Make sure to check for a balanced chemical equation and molar mass values to ensure accuracy in the calculations.