how many grams of NaCl (molecular weight 58.5) should be used to prepare 20 liters of a solution containing 154mEq/L?
For NaCl, 1 equivalent is the same as 1 mole.
154 mEq/L = 0.154 Eq/L = 0.154 mole/L
So you want g = moles x molar mass = 0.154 x 58.5 = grams/L. For 20 L you want 20x that.
If you don't want to go through the conversion each time, just remember that
mEq x milliequivalent weight = grams.
So you want 154 x 0.0585 = ?? grams and that is in 1L, so 20x that is the amount for 20 L.
180.20
Well, to prepare a solution with 154mEq/L, we need to do some calculations. But before that, let me ask you a question: Did you know that sodium and chlorine went for a date? Yeah, they had such great chemistry! They just couldn't separate, I guess. Anyway, back to your question!
To convert milliequivalents (mEq) to grams, we need to know the valence of the ion. In the case of NaCl, both sodium (Na+) and chlorine (Cl-) have a valence of 1. This means that 1 mole of NaCl will have 1 equivalent of Na+ ions and 1 equivalent of Cl- ions.
Now, to calculate the grams of NaCl needed, we can use the formula:
Grams = (mEq/L) x (molecular weight)/(1000)
Substituting the values, we get:
Grams = 154 x 20 x 58.5 / 1000
And if we crunch the numbers, we find that you need approximately 181.32 grams of NaCl.
So, there you have it! Just make sure to measure it carefully, because if you spill a little too much, things might get a little salty in the lab.
To calculate the number of grams of NaCl needed to prepare a solution with a specific concentration, you need to follow a few steps. Here's how you can do it:
1. Determine the molar mass of NaCl: The molecular weight is given as 58.5 grams/mole.
2. Convert milliequivalents (mEq) to moles: Since mEq is a measure of the charge, you need to convert it to moles to perform further calculations. To convert mEq to moles, you need to know the equivalent weight of NaCl. Since NaCl has a 1:1 ratio of sodium (Na) to chloride (Cl) ions, the equivalent weight is equal to the molar mass (58.5 grams/mole).
3. Calculate the number of moles: Since you know the concentration (154 mEq/L) and volume (20 liters), you can multiply them to get the number of moles.
Number of moles = Concentration (mEq/L) × Volume (L)
4. Convert moles to grams: Multiply the number of moles by the molar mass of NaCl (58.5 grams/mole) to find the mass in grams.
Mass (g) = Number of moles × Molar mass (g/mole)
Now, let's calculate the grams of NaCl required:
Number of moles = 154 mEq/L × 20 L = 3080 mEq
Mass (g) = 3080 mEq × (58.5 g/1 mole) = 180,180 grams
Therefore, you would need approximately 180,180 grams of NaCl to prepare 20 liters of a solution with a concentration of 154 mEq/L.