Suppose 24.9 grams of copper (II) nitrate is dissolved in 200. milliliters of a 0.70 moles/liter aqueous solution of sodium chromate.
Calculate the final molarity of nitrate anion in the solution.
24.9g/molar mass Cu(NO3)2 = mols Cu(NO3)2.
There are two mols NO3^- for each mole Cu(NO3)2.
Then M = mols/L soln = mols/0.200L = ?
To calculate the final molarity of nitrate anion (NO3-) in the solution, we need to follow these steps:
Step 1: Calculate the number of moles of copper (II) nitrate (Cu(NO3)2) using its mass and molar mass.
The molar mass of Cu(NO3)2 can be calculated by summing the atomic masses of each element involved:
Copper (Cu) has an atomic mass of 63.55 g/mol.
Nitrogen (N) has an atomic mass of 14.01 g/mol.
Oxygen (O) has an atomic mass of 16.00 g/mol.
The molecular formula of copper (II) nitrate (Cu(NO3)2) contains one copper atom, two nitrogen atoms, and six oxygen atoms.
Molar mass of Cu(NO3)2 = (63.55 g/mol) + 2*(14.01 g/mol) + 6*(16.00 g/mol)
= 63.55 g/mol + 28.02 g/mol + 96.00 g/mol
= 187.57 g/mol
Now, we can calculate the number of moles of copper (II) nitrate using the given mass:
Number of moles = Mass / Molar mass
= 24.9 g / 187.57 g/mol
= 0.1326 mol
Step 2: Calculate the volume of the sodium chromate solution in liters.
The given volume is in milliliters, so we need to convert it to liters:
Volume = 200. milliliters = 200. / 1000 liters = 0.200 L
Step 3: Calculate the number of moles of nitrate anion (NO3-) in the copper (II) nitrate solution.
Since one mole of copper (II) nitrate produces two moles of nitrate anion (NO3-), the number of moles of nitrate anion is twice the number of moles of copper (II) nitrate:
Number of moles of nitrate anion = 2 * 0.1326 mol = 0.2652 mol
Step 4: Calculate the final molarity of nitrate anion (NO3-) in the solution.
Molarity (M) is defined as moles of solute divided by volume of solution in liters. Therefore:
Molarity = Number of moles / Volume
= 0.2652 mol / 0.200 L
= 1.326 M
Therefore, the final molarity of nitrate anion (NO3-) in the solution is 1.326 M.
To calculate the final molarity of the nitrate anion in the solution, we first need to determine the number of moles of copper (II) nitrate that are dissolved in the solution.
1. Calculate the number of moles of copper (II) nitrate:
Number of moles = mass / molar mass
The molar mass of copper (II) nitrate (Cu(NO3)2) can be calculated as follows:
Cu: 63.55 g/mol
N: 14.01 g/mol
O: 16.00 g/mol
So, the molar mass of Cu(NO3)2 = (63.55) + 2*(14.01) + 6*(16) = 187.55 g/mol
Number of moles = 24.9 g / 187.55 g/mol = 0.1327 mol
2. Next, we need to calculate the final volume of the solution after dissolving the copper (II) nitrate. Since 200 mL of a 0.70 mol/L solution of sodium chromate is used, the final volume will be 200 mL.
3. Now, we can calculate the final molarity of nitrate anion:
Molarity = Number of moles / Volume in L
Molarity = 0.1327 mol / (200 mL / 1000 mL/L) = 0.6635 mol/L
Therefore, the final molarity of nitrate anion in the solution is 0.6635 mol/L.