In a typical synthesis reaction, 0.142 g of chlorine gas is reacted with an unkown elemnt X to form a compound with the formula XCl3. If the final product has a mass of 0.178 g, what is the atomic mass of the unknown element?
The guy posting as DrBob222 attempts to make the student do the question out themselves by posting the structure of the question. I hope this guy realizes his psychobabble is not understandable and that he is the bane of students everywhere.
3Cl2 + 2X ==>2XCl3
mols Cl2 = g/molar mass = 0.142/molar mass Cl2.
mols XCl3 = mols Cl2 x (2 mol XCl3/3 mols Cl2)= xx
mols XCl3 = g/molar mass or rearrange to
molar mass = g/mols
Then knowing molar mass and mass Cl3, determine mass X which will be the atomic mass. Look on the periodic table to determine the metal.
Check my work.
To find the atomic mass of the unknown element X, we need to determine the mass of X in the compound XCl3.
We are given the mass of the starting material, chlorine gas (Cl2), which is 0.142 g.
First, we need to determine the number of moles of chlorine gas. To do this, we divide the mass of chlorine by its molar mass. The molar mass of chlorine (Cl2) is calculated by adding the atomic masses of two chlorine atoms together.
The atomic mass of chlorine is 35.45 g/mol. Therefore, the molar mass of Cl2 is 2 * 35.45 g/mol = 70.90 g/mol.
Next, we can calculate the moles of chlorine gas (Cl2):
moles of Cl2 = mass of Cl2 / molar mass of Cl2
moles of Cl2 = 0.142 g / 70.90 g/mol = 0.0020 mol
According to the balanced equation for the synthesis reaction X + 3Cl2 → XCl3, we know that the moles of chlorine (Cl2) equal the moles of X (since the coefficient is 1 for X).
Therefore, moles of X = 0.0020 mol
To find the mass of X, we multiply the moles of X by the molar mass of X (which is the atomic mass we are trying to find).
mass of X = moles of X * molar mass of X
From the problem, the mass of the final product XCl3 is 0.178 g.
Finally, we can rearrange the equation to solve for the atomic mass (molar mass) of X:
molar mass of X = mass of X / moles of X
molar mass of X = 0.178 g / 0.0020 mol
Using a calculator, we find that the molar mass (atomic mass) of X is 89 g/mol. Therefore, the atomic mass of element X is 89 atomic mass units.