posted by Anna on .
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?
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.
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.