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Empirical Formulation of a Compound

16. A compound contains 40.00% carbon, 6.67% hydrogen, and 53.33% oxygen. Determine the empirical formula of the compound.
Please help with the following problems.

1. Give the chemical formula for calcium phosphate.

2. A hypothetical element, Js, has three naturally occurring isotopes. The atomic mass and relative abundance of each isotope are: 35% 191 Js, 20% 185 Js,And 45% 192 Js. What atomic mass should be reported for this element?

3. A gas sample at 75 degrees C and 2.0 atm pressure occupy a volume of 2.5L. What volume will it occupy at STP?

4. Convert 200 degrees C to degrees F.

Solution Preview

1. Assume that you have 100 g (1 g = 1%) of sample, calculate the moles for each element by dividing the mass by the molar mass (n = m/M). For C it will be 3.33 moles, H will be 6.60 moles, and O will be 3.33 moles. Next divide the number of moles for each element by the smallest value for moles, basically we are finding ...

Solution Summary

This posting helps with physical chemistry problems. The solution provides calculations and an explanation in over 200 words.