Balance equation: Ca(s) + O2(g) -> CaO(s) What is the coefficient for CaO in this reaction? A2 Consider the following particulate-level representation of a chemical equation: Ca(s) + O2(g) -> CaO(s) Assume that all spheres represent atoms of A. Which of the following is the correctly balanced equation for this reaction? A2 – 2A -> 2A – 2A + 4 – (A + A) Calcium oxide is produced when calcium reacts with oxygen in the air. Write the balanced chemical equation for this reaction: Ca(s) + O2(g) -> CaO(s) What is the sum of the coefficients? 2 Potassium fluoride is produced when potassium reacts with fluorine. Write the balanced chemical equation for this reaction. What is the coefficient for potassium? K + F2 -> KF, coefficient for potassium = 1<\/p>\n\n\n\n
The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n
Let’s break down the questions step by step:<\/p>\n\n\n\n
1. Balancing the reaction:<\/strong><\/h3>\n\n\n\n
The reaction between calcium and oxygen to form calcium oxide is given by: Ca (s)+O2(g)\u2192CaO (s)\\text{Ca (s)} + \\text{O}_2 \\text{(g)} \\rightarrow \\text{CaO (s)}Ca (s)+O2\u200b(g)\u2192CaO (s)<\/p>\n\n\n\n
To balance this reaction, we need to ensure that the number of atoms on both sides of the equation is the same. Here’s how we do it:<\/p>\n\n\n\n
\n
Step 1:<\/strong> The left side has 1 calcium (Ca) atom, and 2 oxygen (O) atoms from the O\u2082 molecule. The right side has 1 calcium (Ca) atom and 1 oxygen (O) atom in the CaO.<\/li>\n\n\n\n
Step 2:<\/strong> To balance the oxygen atoms, we need to place a coefficient of 2 in front of CaO: Ca\u00a0(s)+O2(g)\u21922CaO\u00a0(s)\\text{Ca (s)} + \\text{O}_2 \\text{(g)} \\rightarrow 2 \\text{CaO (s)}Ca\u00a0(s)+O2\u200b(g)\u21922CaO\u00a0(s)<\/li>\n\n\n\n
Step 3:<\/strong> Now, to balance the calcium atoms, we need to place a coefficient of 2 in front of Ca on the left side: 2Ca\u00a0(s)+O2(g)\u21922CaO\u00a0(s)2 \\text{Ca (s)} + \\text{O}_2 \\text{(g)} \\rightarrow 2 \\text{CaO (s)}2Ca\u00a0(s)+O2\u200b(g)\u21922CaO\u00a0(s)<\/li>\n<\/ul>\n\n\n\n
This gives us the balanced equation: 2Ca (s)+O2(g)\u21922CaO (s)2 \\text{Ca (s)} + \\text{O}_2 \\text{(g)} \\rightarrow 2 \\text{CaO (s)}2Ca (s)+O2\u200b(g)\u21922CaO (s)<\/p>\n\n\n\n
Answer:<\/strong> The coefficient for CaO in the balanced equation is 2.<\/p>\n\n\n\n\n\n\n\n
2. Particulate-level representation of the reaction:<\/strong><\/h3>\n\n\n\n
The question suggests a model where all spheres represent calcium (Ca) atoms. In this case, the balanced equation would be: 2Ca+O2\u21922CaO2\\text{Ca} + \\text{O}_2 \\rightarrow 2\\text{CaO}2Ca+O2\u200b\u21922CaO<\/p>\n\n\n\n
The visual representation would show two calcium atoms reacting with one O\u2082 molecule to produce two CaO units.<\/p>\n\n\n\n
\n\n\n\n
3. Sum of the coefficients:<\/strong><\/h3>\n\n\n\n
In the balanced equation: 2Ca (s)+O2(g)\u21922CaO (s)2\\text{Ca (s)} + \\text{O}_2 \\text{(g)} \\rightarrow 2\\text{CaO (s)}2Ca (s)+O2\u200b(g)\u21922CaO (s)<\/p>\n\n\n\n
The coefficients are 2 (for Ca), 1 (for O\u2082), and 2 (for CaO). The sum of these coefficients is: 2+1+2=52 + 1 + 2 = 52+1+2=5<\/p>\n\n\n\n
Answer:<\/strong> The sum of the coefficients is 5<\/strong>.<\/p>\n\n\n\n\n\n\n\n
4. Balanced equation for potassium fluoride (KF):<\/strong><\/h3>\n\n\n\n
Potassium (K) reacts with fluorine (F\u2082) to form potassium fluoride (KF): K+F2\u2192KF\\text{K} + \\text{F}_2 \\rightarrow \\text{KF}K+F2\u200b\u2192KF<\/p>\n\n\n\n
To balance the equation:<\/p>\n\n\n\n
\n
We need 2 fluorine atoms on the left side, but the right side only has 1 fluorine in KF. So, we place a coefficient of 2 in front of KF: K+F2\u21922KF\\text{K} + \\text{F}_2 \\rightarrow 2\\text{KF}K+F2\u200b\u21922KF<\/li>\n\n\n\n
Now, to balance the potassium atoms, we place a coefficient of 2 in front of K: 2K+F2\u21922KF2\\text{K} + \\text{F}_2 \\rightarrow 2\\text{KF}2K+F2\u200b\u21922KF<\/li>\n<\/ul>\n\n\n\n
Answer:<\/strong> The coefficient for potassium is 2<\/strong>.<\/p>\n\n\n\n\n\n\n\n
5. Final Summary:<\/strong><\/h3>\n\n\n\n
\n
The coefficient for CaO<\/strong> in the balanced calcium-oxygen reaction is 2<\/strong>.<\/li>\n\n\n\n
The sum of the coefficients in the balanced reaction is 5<\/strong>.<\/li>\n\n\n\n
The coefficient for potassium in the balanced potassium-fluorine reaction is 2<\/strong>.<\/li>\n<\/ul>\n\n\n\n<\/figure>\n","protected":false},"excerpt":{"rendered":"
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