# Chemistry Stp

Topics: Oxygen, Acid, Hydrogen Pages: 3 (467 words) Published: February 19, 2011
PROBLEM SOLVING.

1.Calculate how many hydrogen atoms are contained in 2.3g of C2H5OH.
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2.3 x 1023 Hydrogen Atoms - 2.3g * 1mol/6.06g * 6.02 1023 / 1mol

2.An oxide of sulfur contains 60% by mass of oxygen. Determine the empirical formula of the compound.
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3.Ethylene glycol, the substance used in automobile antifreeze, is composed of 38.7 g carbon, 9.7 g hydrogen, and 51.6 g oxygen. a.What is the empirical formula of the compound?
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b.If its molar mass is 62.1 g/mol, what is the molecular formula of ethylene glycol?
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4.The temp in kelvin of 4.0 L of hydrogen is increased by a factor of 3 and the pressure is increased by a factor of 4. Calculate the final volume of the gas.
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5.How many liters of product at 950 mmHg and O°C is produced by the burning of three liters of acetylene (C2H2) at 5 atm and 20°C?
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6.What is the mass of 15 liters of chlorine gas at STP?
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7.Write the balanced equation for each
a.Nitrogen and oxygen react in cylinders of car engines to form nitrogen monoxide.
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b.Nitrogen monoxide is a primary pollutant. After it escapes into the atmosphere, it reacts with oxygen to produce nitrogen dioxide.
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c.Nitrogen dioxide is a secondary pollutant which can react further with oxygen and water in the atmosphere to produce nitric acid, one of the component of acid rain.
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8.The fizz produced when Alka-Seltzer tablet is dissolved in water is due to the reaction of sodium bicarbonate (NaHCO3) and citric acid (H3C6H5O7)
3NaHCO3(aq) + H3C6H5O7(aq) --> 3CO2 + 3H2O + Na3C6H5O7(aq) In a certain experiment, 5.00 g of sodium bicarbonate and 5.00 g of citric acid are allowed to react. a.Which is the limiting reactant? Show solutions to prove your answer.

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b.How many grams of carbon dioxide are formed?
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