Textbook Question
Write chemical equations for the reaction of calcium with the following substances, making sure that the numbers and kinds of atoms are the same on both sides of the equations. If no reaction occurs, write N.R.
(c) Br2
Ch.22 - The Main Group Elements
Chapter 22, Problem 73
Predict the products of the following reactions, and balance the equations so that the numbers and kinds of atoms are the same on both sides of the reaction arrows. (a) Be(s) + Br2(l) → ? (b) Sr(s) + H2O(l) → ? (c) Mg(s) + O2(g) → ?
Verified step by step guidance1
Identify the type of reaction for each equation. For (a) and (c), these are synthesis reactions where two or more reactants combine to form a single product. For (b), it is a single displacement reaction where an element displaces another in a compound.
For reaction (a), Be(s) + Br2(l) → ?, predict the product by combining beryllium and bromine to form beryllium bromide, BeBr2. Write the unbalanced equation: Be(s) + Br2(l) → BeBr2(s).
Balance the equation for reaction (a) by ensuring the number of atoms of each element is equal on both sides. Start by balancing the bromine atoms, then adjust the beryllium atoms if necessary.
For reaction (b), Sr(s) + H2O(l) → ?, predict the products by recognizing that strontium will displace hydrogen in water, forming strontium hydroxide and hydrogen gas: Sr(s) + H2O(l) → Sr(OH)2(aq) + H2(g).
Balance the equation for reaction (b) by ensuring the number of atoms of each element is equal on both sides. Start by balancing the hydrogen atoms, then adjust the strontium and oxygen atoms if necessary.
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Chemical Reactions
Chemical reactions involve the transformation of reactants into products through the breaking and forming of chemical bonds. Understanding the types of reactions, such as synthesis, decomposition, and single or double displacement, is crucial for predicting products. In the given question, recognizing the nature of the reactants helps in determining the likely products formed during the reactions.
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Chemical Properties
Balancing Chemical Equations
Balancing chemical equations is essential to ensure that the law of conservation of mass is upheld, meaning the number of atoms of each element must be the same on both sides of the equation. This involves adjusting coefficients in front of compounds rather than changing subscripts, which would alter the compounds themselves. Mastery of balancing equations is vital for accurately representing chemical reactions.
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Reactivity of Elements
The reactivity of elements, particularly metals and nonmetals, influences the products formed in chemical reactions. For instance, alkali and alkaline earth metals like Be, Sr, and Mg readily react with halogens or water, while metals react with oxygen to form oxides. Understanding the reactivity series helps predict which elements will react and the types of products that will be formed in the reactions presented.
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Related Practice
Textbook Question
Write chemical equations for the reaction of calcium with the following substances, making sure that the numbers and kinds of atoms are the same on both sides of the equations. If no reaction occurs, write N.R.
(d) O2
Textbook Question
Milk of magnesia, a widely used antacid, is an aqueous suspension of Mg1OH22. How would you prepare Mg1OH22 from magnesium metal?