Write balanced chemical equations to correspond to each of the following descriptions: (c) Phosphine, PH3(g), combusts in oxygen gas to form water vapor and solid tetraphosphorus decaoxide.
Ch.3 - Chemical Reactions and Reaction Stoichiometry
Chapter 3, Problem 18a
(a) When a compound containing C, H, and O is completely combusted in air, what reactant besides the hydrocarbon is involved in the reaction?
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Step 1: In a combustion reaction, a substance reacts with oxygen to produce heat and light. The substance that is being combusted is often a hydrocarbon, which is a compound made up of carbon (C), hydrogen (H), and sometimes oxygen (O).
Step 2: Besides the hydrocarbon, the other reactant involved in a combustion reaction is oxygen (O2). This is because combustion is an oxidation reaction, which means it involves the addition of oxygen.
Step 3: The oxygen is usually supplied by the air, which is why combustion reactions often occur when a substance is exposed to air.
Step 4: Therefore, when a compound containing C, H, and O is completely combusted in air, the reactant besides the hydrocarbon that is involved in the reaction is oxygen (O2).
Step 5: The general equation for a combustion reaction is: Hydrocarbon + O2 -> CO2 + H2O. This equation shows that carbon dioxide (CO2) and water (H2O) are the products of a combustion reaction.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Combustion Reaction
A combustion reaction is a chemical process in which a substance reacts rapidly with oxygen, producing heat and light. In the case of hydrocarbons, the primary products are carbon dioxide (CO2) and water (H2O). Understanding this reaction is crucial for identifying the reactants and products involved in the combustion of compounds containing carbon, hydrogen, and oxygen.
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Role of Oxygen
Oxygen is a vital reactant in combustion reactions, particularly for organic compounds like hydrocarbons. It combines with the carbon and hydrogen in the fuel to produce carbon dioxide and water. Recognizing the role of oxygen helps clarify the complete combustion process and the stoichiometry involved in the reaction.
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Stoichiometry of Combustion
Stoichiometry refers to the quantitative relationship between reactants and products in a chemical reaction. In combustion, it is essential to balance the equation to determine the exact amounts of oxygen required for complete combustion of a hydrocarbon. This concept is fundamental for predicting the reactants and products in combustion scenarios.
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Related Practice
Textbook Question
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Textbook Question
Write balanced chemical equations to correspond to each of the following descriptions: (d) When solid mercury(II) nitrate is heated, it decomposes to form solid mercury(II) oxide, gaseous nitrogen dioxide, and oxygen. (e) Copper metal reacts with hot concentrated sulfuric acid solution to form aqueous copper(II) sulfate, sulfur dioxide gas, and water.
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Open Question
(a) When the metallic element lithium combines with the nonmetallic element chlorine, Cl2(g), what is the chemical formula of the product? (b) In the balanced chemical equation for this reaction, what is the coefficient in front of the product if the coefficient in front of Cl2(g) is 1?
Textbook Question
(b) What products form in this reaction?
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Textbook Question
(c) What is the sum of the coefficients in the balanced chemical equation for the combustion of one mole of acetone, C3H6O1l2, in air?
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Textbook Question
Write a balanced chemical equation for the reaction that occurs when (a) Mg(s) reacts with Cl2(g)
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