A 68 g sample of a compound used as a dry cleaning fluid is found to contain 10.80 g carbon, 1.36 g hydrogen and 47.84 g chlorine.  What is the subscript of hydrogen in the empirical formula for the compound?

A sample of a hydrocarbon (a compound consisting of only carbon and hydrogen) contains 2.59 1023 atoms of hydrogen and is 17.3% hydrogen by mass. If the molar mass of the hydrocarbon is between 55 and 65 g/mol, what amount (moles) of compound is present, and what is the mass of the sample?

Vitamin A has a molar mass of 286.4 g/mol and a general molecular formula of CxHyE, where E is an unknown element. If vitamin A is 83.86% C and 10.56% H by mass, what is the molecular formula of vitamin A?

A substance X2Z has the composition (by mass) of 40.0% X and 60.0% Z. What is the composition (by mass) of the compound XZ2?

opical hydrocortisone is often used to treat a variety of skin conditions, such as insect bites, eczema, and rashes. Each molecule of hydrocortisone contains 21 atoms of carbon (plus other atoms). The mass percentage of carbon in hydrocortisone is 69.5 8%. What is the molar mass of hydrocortisone?

Mandelic acid is an organic acid composed of carbon (63.15%), hydrogen (5.30%), and oxygen (31.55%). Its molar mass is 152.14 g/mol. Determine the empirical and molecular formulas of the acid.

Uranium is used as a fuel, primarily in the form of uranium(IV) oxide, in nuclear power plants. This question considers some uranium chemistry. (a) A small sample of uranium metal (0.169 g) is heated to between 800 and 900 C in air to give 0.199 g of a dark green oxide, UxOy How many moles of uranium metal were used? What is the empirical formula of the oxide, UxOy? What is the name of the oxide? How many moles of UxOy must have been obtained? (b) The naturally occurring isotopes of uranium are 234U, 235U, and 238U. Knowing that uraniums atomic weight is 238.02 g/mol, which isotope must be the most abundant? (c) If the hydrated compound UO2(NO3)2 z H2O is heated gently, the water of hydration is lost. If you have 0.865 g of the hydrated compound and obtain 0.679 g of UO2(NO3)2 on heating, how many waters of hydration are in each formula unit of the original compound? (The oxide Ux, Oy is obtained if the hydrate is heated to temperatures over 800C in the air.)

A compound was analyzed and found to contain the following percentages of elements by mass: carbon, 79.89%; hydrogen, 20.11%. l type='a'> Determine the empirical formula of the compound. i>Which of the following could be a molar mass of the compound? 13.018 g/mol 16.042g/mol 28.052 g/mol 30.068 g/mol 104.23 g/rnol

Atomic masses are relative masses. What does this mean?

Acetylene is a colorless gas used as a fuel in welding torches, among other things. It is 92.26% C and 7.74% H. Its molar mass is 26.02 g/mol. What are the empirical and molecular formulas of acetylene?