6. Determine the empirical formula of C3H . O C3H8 C6H6 O CO.5H2 O CH2.5

The compound 1-propanethiol, which is the eye irritant released when fresh onions are chopped up, has the chemical formula C3HyS and a formula mass of 76.18 amu. What number does y stand for in the chemical formula of the compound?

Atomic masses are relative masses. What does this mean?

Arrange the following substances in order of increasing mass percent of nitrogen. a. NO b. N2O c. NH3 d. SNH

You have a pure sample of the antiseptic aminacrine, C13H10N2. Calculate the mass in grams of 0.06500 mol aminacrine. Calculate the number of aminacrine molecules in a 0.2480-g sample. Calculate the number of nitrogen atoms in this 0.2480-g sample. Calculate the mass of N in 100. g aminacrine.

2.37 Why are empirical formulas preferred for describing polymer molecules?

A compound called MMT was once used to boost the octane rating of gasoline. What is the empirical formula of MMT if it is 49.5% C, 3.2% H, 22.0% O, and 25.2% Mn?

3.123 Most periodic tables provide molar masses with four or five significant figures for the elements. How accurately would you have to measure the mass of a sample of roughly 100 g to make a calculation of the number of moles of the chemical to have its significant figures limited by the molar mass calculation rather than the mass measurement?

n chemistry, what is meant by the term mole? What is the importance of the mole concept?

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.)