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Chemical Quantities Problems

Please provide the exact steps that are involved in solving each of these problems and how to arrive at the answers step-by-step so I can grasp the concept clearly.

1. The gaseous hydrocarbon acetylene, C2H2, is used in welders torches because of the large amount of heat released when acetylene burns with oxygen, producing carbon dioxide and water. First, write a balanced equation for the combustion of acetylene in oxygen. then, how many grams of oxygen are needed for the complete combustion of 150 grams of acetylene. How many carbon dioxide molecules are formed in this reaction.

2. With the news that calcium deficiencies in many women's diets may contribute to the development of osteoporosis, the use of dietary calcium supplements has become increasingly common. Many of these calcium supplements consist of nothing more than calcium carbonate. When a calcium carbonate tablet is ingested, it dissolves by the reaction of stomach acid, which contains hydrochloric acid. The unbalanced equation for this reaction is CaCO3 +HCl ----> H2O +CO2. What mass of HCL is required to react with a tablet containing 500 milligrams of calcium carbonate?

3.the formula for thionyl chloride is SOCL2. this compound is a very powerful drying agent in the synthetic chemistry industry in that it reacts completely with water according to the following unbalanced equation: SOCl2 +H2O----> SO2 +HCL. How many water molecules can 35.0 grams of thionyl chloride remove?

4.An experiment that led to the formation of the new field of organic chemistry involved the synthesis of urea, CN2H4O by the controlled reaction of ammonia and carbon dioxide: gaseous ammonia + gaseous carbon dioxide -----> solid urea + liquid water. What is the maximum yield of urea in moles when 100 grams of ammonia and 100 grams of carbon dioxide are reacted?

5. One process for the commercial production of baking soda, sodium hydrogen carbonate, involves the following reaction: aqueous sodium chloride + gaseous ammonia + solid sodium hydrogen carbonate. Because they are relatively cheap, sodium chloride and water are typically present in excess. What is the theoretical yield of sodium hydrogen carbonate when one performs such a synthesis using 10.0 grams of ammonia and 15.0 grams of solid carbon dioxide, with an excess of water and sodium chloride?

6. If an instructor takes samples of iron and sulfur and just mixes them together, the two elements can be separated from on another with a magnet. If the instructor then combines and heats the mixture of iron and sulfur, a chemical reaction takes place and the elements combine to form iron(II) sulfide, which is not magnetic. First, write a balanced equation for this reaction. Then calculate the theoretical yield if 5.25 grams of iron is reacted with 12.7 grams of sulfur. Finally, calculate the % composition of the newly formed compound.

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I need the exact steps that are involved in solving each of these problems and how to arrive at the answers step by step so I can grasp the concept clearly.

1. The gaseous hydrocarbon acetylene, C2H2, is used in welders torches because of the large amount of heat released when acetylene burns with oxygen, producing carbon dioxide and water. First, write a balanced equation for the combustion of acetylene in oxygen. then, how many grams of oxygen are needed for the complete combustion of 150 grams of acetylene. How many carbon dioxide molecules are formed in this reaction.

2C2H2 + 5O2 → 2H2O + 4CO2
Mol wt of acetylene = 2*12 + 2*1 = 26 grams/moles
Number of moles of acetylene in 150 grams = 150/26 = 5.769 moles
2 moles of acetylene react with 5 moles of oxygen
Therefore, 5.769 moles of acetylene would react with 5.769*5/2 = 14.423 moles of oxygen
1 mole of oxygen weighs 32 grams
Therefore, 14.423 moles of oxygen would weigh = 32*14.423 = 461.54 grams of oxygen
2 moles of acetylene form 4 moles of carbon dioxide
Therefore, 5.769 moles of acetylene would form 5.769*4/2 = 11.538 moles of CO2
One mole of CO2 has 6.022*1023 molecules
Therefore, 11.538 moles of CO2 would have 11.538*6.022*1023 molecules
= 6.948*1024 molecules of CO2.

2. With the news that calcium deficiencies in many women's diets may contribute to the development of osteoporosis, the use of dietary calcium supplements has become increasingly common. Many of these calcium supplements consist of nothing more than calcium carbonate. When a calcium carbonate tablet is ingested, it dissolves by ...

Solution Summary

The solution determines the chemical quantities in the given questions.

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