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Reaction Stoichiometry

Reaction Stoichiometry refers to the examination of the relative abundances of reactants and products in a chemical reaction within a defined system. In order to use reaction stoichiometry to calculate desired quantitative data, it is important to first understand the relationships between the reactants and the products. This requires the process of balancing reactions, which is usually the most important step when doing stoichiometric calculations.

To balance an equation, it is necessary that there are the same number of atoms in the reactants as there are in the products. One can do this by raising the coefficients of individual reactants or products.

For example, the combustion of methane involves reacting methane (CH4) and oxygen (O2) to form carbon dioxide (CO2) and water (H2O). The unbalanced chemical equation can be written as:

CH4(g) + O2(g) --> CO2(g) + H2O(l)

It can be seen that the number of atoms on each side are unbalanced; and so raising the coefficients of O2 and H2O to 2 will balance the equation for the combustion reaction:

CH4(g) + 2O2(g) --> CO2(g) + 2H2O(g)

Thus, from these stoichiometric coefficients, it can be seen that 1 mole of methane reacts with 2 moles of molecular oxygen to form 1 mole of carbon dioxide and 2 moles of water. Using these relative ratios, one can hypothetically say that 0.1 moles of methane requires 0.2 moles of oxygen or 0.6 moles of methane requires 1.2 moles of oxygen. Therefore, understanding the relationship between reactants and products is absolutely fundamental to run stoichiometric calculations on chemical reactions.

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Balance Equations and Mass Percent

Problem: Iodine is present in Chilean saltpeter as iodate anion (IO3-). The amount of iodate anion in a particular sample may be determined by dissolving the sample and then reacting the IO3-(aq) with excess aqueous sodium bisulfite (NaHSO3(aq)) via: 2 IO3-(aq) + NaHSO3 (aq) -----> I2(aq) + Na+(aq) + 5SO4-2(aq) + H+(aq) + H2O(l)

Dinitrogen pentoxide gas reacts with water

Dinitrogen pentoxide gas reacts with water to produce aqueous nitric acid. If 54.1mL of water react with 600 g of dinitrogen pentoxide, how many grams of nitric acid will be produced? Assume water has a density of 1.00g/mL. [Remember to use the correct number of significant figures and write the answer in scientific notatio

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In equation: N2+3H2 > 2NH3, how many moles of hydrogen are required to produce 556g ammonia?

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Zirconium is obtained industrially using the Kroll process. The Kroll process is a pyrometallurgical process used initialy to produce titanium and later developed to produce zirconium. It is a high temperature process that combines zirconium (IV) chloride with magnesium metal to produce zirconium metal and magnesium chloride via

Stoichiometry and Multiplying Electrons

Complete and balance the following reaction: As(s)+ClO3^-(aq) (right arrow) H3AsO3(aq)+HCLO (aq) I have the following options: -split into 1/2 reactions -balance all but H and O -balance O by adding H20 -balance H+ by adding protons -balance charge by adding electrons I am stuck, after adding equations to get electro

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I need help on how to balance redox reactions in a systematic way. I already have the answers, I need to know step-by-step how to get there...thanks! Example: cCmplete and balance the following reaction: H2O2+Cl2O7 (right arrow) Clo2^- +O2 (which occurs in basic solution) Also - how do you tell what was oxidized and what wa

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In a location in Florida, water seeping into the ground contains 50 times as much carbon dioxide as rainwater. This ground water passes through a limestone deposit and ultimately into an underground spring. The spring has a flow rate of 2500 liters per second. How much limestone (CaCO3) in metric tons will be dissolved in thi

Stoichiometry

I have a couple of problems that I am struggling with. For the reaction 2NO+O2->2 NO2 what is the maximum amount (in g's) of NO2 which could be formed from 6.49g of NO and 18.8 g or O2? For the reaction 2CO+O2->2CO2 what is the maximum amount (in units of mol.) of CO2 which could be formed from 16.02g of CO and 1.16g of

Using Stoichiometry Ratios

Reaction: 5C + 2SO2 -> CS2 + 4CO Questions: 1) How many moles of CS2 are there for when 2.7 moles of C reacts? 2) How many moles of carbon are needed to react with 5.44 moles of SO2? 3) How many moles of carbon monoxide form at the same time that .246 moles of CS2 forms? 4) How many moles of SO2 are required to make 118

Stoichiometry Question

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