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What volume (in liters) is occupied by [m] g of methane, CH4, at [t]  oC and [p] atm?

Give (in order) the correct coefficients to balance the following reaction:H2SnCl6  +    H2S →  SnS2  +    HCl

An oxygen sample has a volume of [v] L at [t] oC and [p] torr.  How many oxygen molecules does it contain?

The molar mass of an insecticide, dibromoethane, is 187.9.  Its molecular formula is C2H4Br2.  How many atoms of carbon are in a sample of dibromoethane weighing [m] g?

When 19.8 g C2H6 and [m] g O2 react to form CO2 and H2O, how many grams of water are formed? Make sure you balance the equation first.  C2H6  +  O2  →  CO2  + H20

A sample of an element with a mass of [m] g was dropped in a graduated cylinder containing 22.30 mL water.  The volume of the water plus the sample was [v] mL.  What is the density of the element?

A scientist obtains the number 0.045006700 on a calculator. If this number actually has four (4) significant figures, how should it be written?

As part of the calibration of a new laboratory balance, a 1.000-g mass is weighed with the following results: Trial …. Mass 1 ……… 1.201 ± 0.001 2 ………..1.202 ± 0.001 3 ………..1.200 ± 0.001            The balance is:

Which of the following hormones is primarily responsible for increasing glucose availability during prolonged exercise?

A [m]-g sample of HF is dissolved in water to give [v] mL of solution.  The concentration of the solution is: (answer in molarity)