gogogadget
New member
- Joined
- Jan 29, 2012
- Messages
- 8
Hello so I am having issues with trying to successfully convert between units between these two problems. My prof has provided the answers but didn't provide the calculations needed to get it.
1. You have a 1M Tris (pH 8.0) stock solution and you want to make 250 ml of 100mM Tris (pH 8.0). How will you make your solution?
I started with 250 mL and divided by 1000 mL to get to one L. From there, converted the L to M as M = mol per liter. She provided info in that the density of Tris base is 121.2 g which I know is equal to one mole. From there though, I cannot figure out what to do with 100 mM or how to convert to it. Is it milli moles or milli M (mol/liter). I kept getting an answer at around 30 but my professor's answer was to add 25 mL of 1 M Tris (pH 8.0) to 225 mL of water.
2. 1x TE is 10mM Tris (pH 8.0) and 1mM EDTA. How would you make 500 ml of 1x TE from stock solutions of 1M Tris (pH 8.0) and 0.5M EDTA?
From this problem, it appears that two seperate calculations will be made. However, again I am stumped on what to do with mM....Any help would be really appreciated! My professor's answer for this one was to add 5 mL of 1 M Tris (pH 8.0) and 1 mL of 0.5 M EDTA to 494 mL of water.
1. You have a 1M Tris (pH 8.0) stock solution and you want to make 250 ml of 100mM Tris (pH 8.0). How will you make your solution?
I started with 250 mL and divided by 1000 mL to get to one L. From there, converted the L to M as M = mol per liter. She provided info in that the density of Tris base is 121.2 g which I know is equal to one mole. From there though, I cannot figure out what to do with 100 mM or how to convert to it. Is it milli moles or milli M (mol/liter). I kept getting an answer at around 30 but my professor's answer was to add 25 mL of 1 M Tris (pH 8.0) to 225 mL of water.
2. 1x TE is 10mM Tris (pH 8.0) and 1mM EDTA. How would you make 500 ml of 1x TE from stock solutions of 1M Tris (pH 8.0) and 0.5M EDTA?
From this problem, it appears that two seperate calculations will be made. However, again I am stumped on what to do with mM....Any help would be really appreciated! My professor's answer for this one was to add 5 mL of 1 M Tris (pH 8.0) and 1 mL of 0.5 M EDTA to 494 mL of water.