70 likes | 234 Views
Molecular Formula. What is it?. Simplest formula just shows a ratio of atoms in a substance Simplest formula may or may not be the true molecular formula If you know the true mass of a substance, you can determine if the simplest formula is the molecular formula. Example 1.
E N D
What is it? • Simplest formula just shows a ratio of atoms in a substance • Simplest formula may or may not be the true molecular formula • If you know the true mass of a substance, you can determine if the simplest formula is the molecular formula
Example 1 • The simplest formula of a substance is P2O5. Experiments find it’s mass to be 283.889 g/mole. What is it’s molecular formula?
Example 2 • A sample of a compound contains 1.18g H and 7.06g C. It is found to have a mass of 56.107g/mole. What is its molecular formula?
Practice 1) What is the molecular formula of a compound having a simplest formula of CH and a mass of 78.110 g/mole? 2) A compound consisting of 85.64% C and 14.36% H is found to have a mass of 42.08 g/mole. What is it’s molecular formula?
3) If 4.04 g of N combines with 11.46 g O to produce a compound with a mass of 108.0 g/mole, what is it’s molecular formula? 4) The mass of a compound is 92 g/mole. Analysis shows the compound contains .606 g N and 1.39 g O. What is it’s molecular formula?
5) A compound is found to contain 63.52% iron and 36.48% sulfur. If it’s mass is 175.826 g/mole, what is it’s molecular formula?