Consider an alloy that is 14.1% copper by mass in tin. Copper makes up what percentage of the atoms in this sample?
To determine the percentage of copper atoms in the alloy, we need to calculate the number of moles of copper and the number of moles of tin. Then, we can compare the ratios of moles to calculate the percentage.
1. Obtain the molar masses of copper (Cu) and tin (Sn) from the periodic table:
- Molar mass of Cu = 63.55 g/mol
- Molar mass of Sn = 118.71 g/mol
2. Convert the given percentage mass of copper in the alloy to grams:
- Let's assume we have 100 grams of the alloy.
- Mass of copper = 14.1% of 100 g = 14.1 g
3. Calculate the number of moles of copper and tin:
- Moles of Cu = mass of Cu / molar mass of Cu = 14.1 g / 63.55 g/mol
- Moles of Sn = mass of Sn / molar mass of Sn
= (100 g - 14.1 g) / 118.71 g/mol
4. Calculate the ratio of moles:
- Ratio of moles of Cu to Sn = Moles of Cu / Moles of Sn
5. Convert the ratio of moles to a percentage:
- Percentage of Cu = (Ratio of moles of Cu / (Ratio of moles of Cu + 1)) * 100
Now, let's substitute the values into the equations to find the percentage of copper atoms:
Molar mass of Cu = 63.55 g/mol
Molar mass of Sn = 118.71 g/mol
Mass of Cu = 14.1 g
Mass of Sn = 100 g - 14.1 g = 85.9 g
Moles of Cu = 14.1 g / 63.55 g/mol
Moles of Sn = 85.9 g / 118.71 g/mol
Ratio of moles of Cu to Sn = Moles of Cu / Moles of Sn
= (14.1 g / 63.55 g/mol) / (85.9 g / 118.71 g/mol)
Percentage of Cu = (Ratio of moles of Cu / (Ratio of moles of Cu + 1)) * 100
By calculating these values, we can determine the percentage of copper atoms in the alloy.
To determine the percentage of copper atoms in the sample, we need to first calculate the number of moles of copper and tin in the alloy, and then compare their ratios at the atomic level.
1. Start by assuming you have a 100g sample of the alloy. This means there are 14.1g of copper and 85.9g of tin.
2. Calculate the number of moles for each element using their atomic mass. The atomic mass of copper is 63.55 g/mol, and the atomic mass of tin is 118.71 g/mol.
Moles of copper = mass of copper / atomic mass of copper
= 14.1g / 63.55 g/mol
Moles of tin = mass of tin / atomic mass of tin
= 85.9g / 118.71 g/mol
3. Now, determine the ratio of moles of copper to moles of tin. Divide the moles of copper by the moles of tin.
Ratio = moles of copper / moles of tin
4. Finally, convert this ratio to a percentage by multiplying by 100.
Percentage of copper atoms = Ratio * 100
The resulting percentage will be the percentage of copper atoms in the alloy.
Take a 100 g sample. That will be 14.1 grams Cu and 85.9 g Sn.
mols Cu = 14.1/63.55 = 0.222
mols Sn = 85.9/118.7 = 0.724
atoms Cu = mols x 6.02E23 = 0.222 x 6.02E23 = 1.34E23
atoms Sn = 0.724 x 6.02E23 = 4.36E23
%Cu by atoms = (atoms Cu/total atoms)*100 = ?
Check all of those numbers including the atomic masses.