O is a dibasic acid H2X .G is a solution containing 1.00g of NaOH in 250cm³ solution.
1) calculate the concentration of G in mol/dm³
2) calculate the concentration of O in mol /dm³
3) molar mass of acid given that 100cm³ of O contains 0.485g of the acid
1. G contains 1.00 g NaOH/250 cc. That will be 4.00 g/dm^3 [that's 1.00 g x (1,000 cc/250 cc = 4.00 g/dm^3]
mols NaOH = grams NaOH/molar mass NaOH =4.00/40 = 0.1 mol/dm^3
2. Can't do 2 in moles/dm^3. 3 says it is 4.85 g/dm^3 but no way to calculate moles.
3. Can't do molar mass. Must have moles to do molar mass.
Step 1: Calculate the concentration of G in mol/dm³.
1. Convert the mass of NaOH to moles:
- Molar mass of NaOH = 22.99 g/mol (sodium) + 16.00 g/mol (oxygen) + 1.01 g/mol (hydrogen) = 39.99 g/mol
- Moles of NaOH = mass of NaOH / molar mass of NaOH = 1.00 g / 39.99 g/mol
2. Convert the volume of the solution from cm³ to dm³:
- Volume of G = 250 cm³ = 250/1000 dm³
3. Calculate the concentration (C) of G in mol/dm³ using the formula:
C = moles of solute / volume of solution in dm³
- C = (moles of NaOH) / (volume of G)
Step 2: Calculate the concentration of O in mol/dm³.
1. Dibasic acid H2X means there are two moles of O per mole of acid (H2X).
2. Since 1 mole of NaOH reacts with 2 moles of acid (H2X), the concentration of NaOH in mol/dm³ is also the concentration of O in mol/dm³.
Step 3: Calculate the molar mass of acid given that 100cm³ of O contains 0.485g of the acid.
1. Convert the volume of O from cm³ to dm³:
- Volume of O = 100 cm³ = 100/1000 dm³
2. Calculate the moles of O using its concentration (from Step 2) and volume:
- Moles of O = concentration of O (from Step 2) * volume of O
3. Calculate the molar mass of the acid:
- Molar mass of acid = mass of acid / moles of acid
- Mass of acid = 0.485g (given)
- Moles of acid = 2 * moles of O (since there are 2 moles of O per mole of acid)
Substitute the given values into the equation to find the molar mass of the acid.
To calculate the concentration of a solution, we need to know the number of moles of solute (substance dissolved) and the volume of the solution.
1) To calculate the concentration of solution G in mol/dm³:
Since we have 1.00g of NaOH, we need to convert it to moles. The molar mass of NaOH is 22.99g/mol + 16.00g/mol + 1.01g/mol = 39.99g/mol.
To calculate the number of moles of NaOH, divide the mass by the molar mass:
moles of NaOH = 1.00g / 39.99g/mol = 0.0250 mol
The volume of the solution G is given as 250 cm³ or 0.250 dm³ (since 1 dm³ = 1000 cm³).
Now divide the moles of NaOH by the volume of the solution in dm³:
Concentration of solution G = moles of NaOH / volume of solution G
= 0.0250 mol / 0.250 dm³ = 0.100 mol/dm³
2) To calculate the concentration of dibasic acid O in mol/dm³:
The chemical formula for the dibasic acid is H2X, which means each molecule of the acid contains 2 moles of protons. Since NaOH is a strong base that reacts with acids in a 1:2 molar ratio, we know that the number of moles of NaOH is equal to twice the number of moles of acid (H2X).
Concentration of acid O = Concentration of NaOH / 2 = 0.100 mol/dm³ / 2 = 0.050 mol/dm³
3) To calculate the molar mass of the acid O:
We are given that 100 cm³ of O contains 0.485g of the acid.
First, convert 100 cm³ to dm³: 100 cm³ / 1000 cm³/dm³ = 0.100 dm³.
Now, divide the mass of the acid by the volume of O in dm³:
Molar mass of acid O = mass of acid in g / volume of O in dm³
= 0.485g / 0.100 dm³ = 4.85 g/dm³
Therefore, the molar mass of the dibasic acid O is 4.85 g/dm³.