Ex: [Cu] in river is 30 ppb, what is the molar concentration?
Well, if you've got some copper (Cu) hanging out in the river, it's time to start a new trend: river bling! Now, to answer your question, the molar concentration refers to the number of moles of a substance in a given volume of solution. In this case, we know that the concentration of Cu in the river is 30 parts per billion (ppb). So, to find the molar concentration, you'll need to know the molar mass of copper and the volume of the river water. Once you have those, you can do some mathematical magic to determine the molar concentration. Now go out there and make those rivers shine!
To find the molar concentration given the concentration in parts per billion (ppb), you can follow these steps:
Step 1: Convert the concentration from ppb to moles per liter (mol/L).
Given concentration: 30 ppb
To convert ppb to mol/L, you need to know the molar mass of the element. The molar mass of copper (Cu) is approximately 63.55 g/mol.
To convert ppb to mol/L, use the following formula:
Molar concentration (mol/L) = (Concentration in ppb * 10^(-9)) / Molar mass (g/mol)
Substituting the given values into the formula:
Molar concentration (mol/L) = (30 ppb * 10^(-9)) / 63.55 g/mol
Step 2: Calculate the molar concentration
Molar concentration (mol/L) = (30 * 10^(-9)) / 63.55
Using a calculator, you can evaluate this expression to find the molar concentration.
Please note that ppb is a unit of concentration that represents parts per billion, which means one part per billion. In contrast, molar concentration is expressed in moles per liter (mol/L), which represents the number of moles of a substance per liter of solution.
To calculate the molar concentration from the given parts per billion (ppb), you need to convert it to molarity. Here's how you can do it:
1. Start by converting the ppb value to parts per million (ppm). Since 1 ppb is equal to 1 part in 1 billion parts, and 1 ppm is equal to 1 part in 1 million parts, you can multiply the ppb value by 1000 to get the ppm value.
In this case, [Cu] = 30 ppb = 30 * 1000 = 30,000 ppm.
2. Next, convert the ppm value to molarity. To do this, you need to know the atomic mass of copper (Cu). The atomic mass of Cu is approximately 63.55 g/mol.
Molarity (M) is defined as the number of moles of solute (in this case Cu) per liter of solution. To find the molar concentration, you first need to convert ppm to grams per liter (g/L) using the molar mass of Cu.
Conversion formula: ppm to g/L = (ppm * atomic mass of Cu) / 1,000,000
In this case: g/L = (30,000 ppm * 63.55 g/mol) / 1,000,000 = 1.9065 g/L.
3. Finally, convert grams per liter (g/L) to molar concentration (M). Since the molar mass of Cu is 63.55 g/mol, you can divide the grams per liter by the molar mass to get the molar concentration.
Molar concentration (M) = grams per liter (g/L) / molar mass (g/mol)
In this case: M = 1.9065 g/L / 63.55 g/mol = 0.03 M.
Therefore, the molar concentration of Cu in the river is 0.03 M.
30 grams per billion grams of solution. Well, assuming the density of water is 1000g/liter, then
30/1E9 *1E3=30E-6 or 3E-5 parts per liter.
Now, the moles of Cu in one liter:
must be 30E-6/atomicmassCu=30/63.6 E-6
or .47E-6 moles per liter, or M=.47microMolesperliter