1) Prepare 100mL of 10%w/w HCl from 37%concentrated HCl(density of 37%HCl =1.19g/ml)
2) Prepare 100mL of 10%w/v HCl from 37%
concentrated HCl(density of 37%HCl=1.19g/ml)
Can you please show the calculation steps for 1) & 2)?
Is 10%w/v HCl the same as 10%w/w HCl?
Thanks.
10% w/w means 10 g HCl in 100 g of solution.
10% w/v means 10 g HCl in 100 mL of solution.
Concd HCl has what mass HCl in 1000 mL? That is 1.19 g/mL x 1000 mL x 0.37 = 440.3g. That's 440.3 g HCl/1000 mL of soln. That is the same as 44.03 g HCl/100 mL of soln. We want 10 g/100 mL soln so how much soln should we take of this more concd one?
100 mL x 10/44.03 = 22.7 mL of the concd soln will provide the 10 g and you add water to make 100 mL final soln. That should be 10% w/v.
For the 10% w/w.
Concd HCl is 37% w/w; therefore, it contains 37 g HCl/100 g soln. You want 10 g so 100 x 10/37 = 27.02 g (notice that this is 27.02/1.19 = 22.7 mL from the above preparation). Then add enough water to make 100 g of soln (which will be 100-27.02 = 72.98g H2O). I don't know if this is acceptable or not since this will NOT be 100 mL but it will be close. I looked up the density of 10% HCl and it is 1.05 g/mL so 100 g will have a volume of about 95 mL. Since the problem did not give the density of the 10% soln, I assume this is what your prof wanted. If not you can correct it knowing the density of 10% HCl is 1.05 g/mL. I have used too many significant figures in the final numbers; you should correct that for your work.
Oh, chemistry questions! You're in for a treat! Now, let's break it down step by step:
1) First, we need to find out how much 37% concentrated HCl we need to use. Since the density of 37% HCl is 1.19 g/ml, we multiply the volume (100 mL) by the density (1.19 g/ml) to get the mass: 100 mL * 1.19 g/mL = 119 g.
Now, to calculate how much pure HCl is present in the 37% solution, we multiply the mass (119 g) by the percentage of HCl (37%) and divide by 100: 119 g * 37 / 100 = 44.03 g.
So, we need 44.03 g of pure HCl for the final solution. To find out how much water we need, we subtract the mass of HCl from the total mass: 119 g - 44.03 g = 74.97 g.
Therefore, we need 44.03 g of concentrated HCl and 74.97 g of water to make 100 mL of 10%w/w HCl solution.
2) Now, for 10%w/v HCl, the volume percentage is calculated differently. We know that 10%w/v means 10 grams of HCl in 100 mL of solution.
So, we take the mass percentage of the 37% HCl solution (37%) and multiply it by the density (1.19 g/mL): 37% * 1.19 g/mL = 44.03 g/100 mL.
This means that 100 mL of the 37% HCl solution contains 44.03 g of HCl. Now, to prepare 100 mL of 10%w/v HCl, we take 10% of the 44.03 g: 10% * 44.03 g = 4.403 g.
Therefore, we need 4.403 g of the 37% HCl solution, and we can adjust the volume to 100 mL by adding water.
Now, to answer your last question, no, 10%w/v HCl is not the same as 10%w/w HCl. The "w/v" stands for weight/volume, which means it is a weight percentage in a given volume. On the other hand, "w/w" stands for weight/weight, which is a weight percentage in relation to the total weight.
Hope this explanation didn't make you feel too HCl-mented!
Sure! I can help you with that. Let's start with the calculation steps for both scenarios:
1) To prepare 100mL of 10%w/w HCl from 37% concentrated HCl:
Step 1: Determine the required amount of 37% HCl:
We want to prepare a 10% HCl solution, which means the weight of HCl should be 10% of the total solution weight. In this case, the total solution weight is 100g (100mL of water has an approximate weight of 100g).
Therefore, 10% of 100g is 10g. So, we need 10g of HCl in the final solution.
Step 2: Calculate the volume of 37% HCl needed:
To do this, we need to convert the weight of HCl (10g) to volume using the density of 37% HCl.
The density of 37% HCl is given as 1.19g/mL.
Using the relationship density = mass/volume, we can rearrange the equation to solve for volume:
Volume = Mass / Density
Volume = 10g / 1.19g/mL
Volume ≈ 8.40 mL
So, you will need approximately 8.40 mL of 37% HCl for the preparation.
2) To prepare 100mL of 10%w/v HCl from 37% concentrated HCl:
Step 1: Determine the required amount of 37% HCl:
Again, we want to prepare a 10% HCl solution, which means the weight of HCl should be 10% of the total solution weight. In this case, the total solution volume is 100 mL.
Therefore, 10% of 100mL is 10 mL. So, we need 10 mL of HCl in the final solution.
Step 2: Calculate the weight of 37% HCl needed:
To do this, we need to convert the volume of HCl (10 mL) to weight. The density of 37% HCl is given as 1.19g/mL.
Weight = Volume × Density
Weight = 10 mL × 1.19 g/mL
Weight = 11.9g
So, you will need approximately 11.9g of 37% HCl for the preparation.
To answer your last question, no, 10%w/v HCl is not the same as 10%w/w HCl. The "w/v" stands for weight/volume, which means the concentration is expressed as a percentage of weight of solute (HCl) to volume of solution. On the other hand, "w/w" stands for weight/weight, which means the concentration is expressed as a percentage of weight of solute to weight of solution. In this case, the solution is water.
Sure! I can help you with the calculations for both scenarios.
1) To prepare 100mL of 10%w/w HCl, we need to determine the amount of 37% concentrated HCl required.
The formula to calculate weight/weight percent is:
%w/w = (mass of solute / mass of solution) * 100
Given that we want 100mL of solution, the mass of the solution will be equal to its volume multiplied by its density:
Mass of 100mL of 37% HCl = 100 mL * 1.19 g/mL = 119 grams
Let's assume x grams of the 37% HCl will be used. According to the %w/w formula:
10% = (x / 119) * 100
To solve for x, we can rearrange the equation:
x = 10 / 100 * 119
x = 11.9 grams
Therefore, to prepare 100mL of a 10%w/w HCl solution, you need to measure 11.9 grams of the 37% HCl and then add enough water to make the final volume 100mL.
2) Now, let's calculate how to prepare 100mL of 10%w/v HCl using the same 37% concentrated HCl.
The formula to calculate weight/volume percent is:
%w/v = (mass of solute / volume of solution) * 100
Again, we want 100mL of solution, so we can directly calculate the mass of the HCl using the %w/v formula:
10% = (x / 100) * 100
To solve for x, we can rearrange the equation:
x = 10 / 100 * 100
x = 10 grams
Therefore, to prepare 100mL of a 10%w/v HCl solution, you need to measure 10 grams of the 37% HCl and then add enough water to make the final volume 100mL.
To answer your question, no, 10%w/v HCl is not the same as 10%w/w HCl. In the first case, the weight percent is based on the weight of the solute relative to the weight of the entire solution. In the second case, the weight percent is based on the weight of the solute relative to the volume of the solution.
I hope this helps! Let me know if you have any further questions.