Balance Chemical Equations - Chemistry
Card 1 of 30
Identify the balanced form of: $\text{SO}_2 + \text{O}_2 \rightarrow \text{SO}_3$.
Identify the balanced form of: $\text{SO}_2 + \text{O}_2 \rightarrow \text{SO}_3$.
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$2\text{SO}_2 + \text{O}_2 \rightarrow 2\text{SO}_3$. Need coefficient 2 to balance sulfur atoms.
$2\text{SO}_2 + \text{O}_2 \rightarrow 2\text{SO}_3$. Need coefficient 2 to balance sulfur atoms.
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What law is satisfied when a chemical equation is balanced?
What law is satisfied when a chemical equation is balanced?
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Law of conservation of mass. Mass cannot be created or destroyed in chemical reactions.
Law of conservation of mass. Mass cannot be created or destroyed in chemical reactions.
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Identify the balanced form of: $\text{Cu} + \text{AgNO}_3 \rightarrow \text{Cu(NO}_3)_2 + \text{Ag}$.
Identify the balanced form of: $\text{Cu} + \text{AgNO}_3 \rightarrow \text{Cu(NO}_3)_2 + \text{Ag}$.
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$\text{Cu} + 2\text{AgNO}_3 \rightarrow \text{Cu(NO}_3)_2 + 2\text{Ag}$. Single displacement: Cu replaces Ag in solution.
$\text{Cu} + 2\text{AgNO}_3 \rightarrow \text{Cu(NO}_3)_2 + 2\text{Ag}$. Single displacement: Cu replaces Ag in solution.
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When balancing, which elements should typically be balanced last: single elements or $\text{H}$ and $\text{O}$?
When balancing, which elements should typically be balanced last: single elements or $\text{H}$ and $\text{O}$?
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$\text{H}$ and $\text{O}$ are typically balanced last. Balance complex atoms first, simple elements last.
$\text{H}$ and $\text{O}$ are typically balanced last. Balance complex atoms first, simple elements last.
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Which statement best defines a balanced chemical equation in terms of atoms?
Which statement best defines a balanced chemical equation in terms of atoms?
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Same number of each type of atom on both sides. Conservation of mass requires equal atoms on each side.
Same number of each type of atom on both sides. Conservation of mass requires equal atoms on each side.
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What is the only part of a chemical equation you are allowed to change when balancing?
What is the only part of a chemical equation you are allowed to change when balancing?
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Coefficients (numbers in front of formulas). Coefficients adjust quantities without changing chemical identity.
Coefficients (numbers in front of formulas). Coefficients adjust quantities without changing chemical identity.
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What must never be changed when balancing a chemical equation: coefficients or subscripts?
What must never be changed when balancing a chemical equation: coefficients or subscripts?
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Subscripts must never be changed. Changing subscripts creates different compounds.
Subscripts must never be changed. Changing subscripts creates different compounds.
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What does a coefficient multiply in a chemical formula, for example $3\text{H}_2\text{O}$?
What does a coefficient multiply in a chemical formula, for example $3\text{H}_2\text{O}$?
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All atoms in the entire formula unit. Coefficient multiplies the entire formula unit.
All atoms in the entire formula unit. Coefficient multiplies the entire formula unit.
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In $2\text{Al}_2(\text{SO}_4)_3$, how many sulfur atoms are present in total?
In $2\text{Al}_2(\text{SO}_4)_3$, how many sulfur atoms are present in total?
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$6\text{ S atoms}$. 2 × 3 × 1 = 6 sulfur atoms from the sulfate ions.
$6\text{ S atoms}$. 2 × 3 × 1 = 6 sulfur atoms from the sulfate ions.
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In $3\text{Ca}(\text{OH})_2$, how many oxygen atoms are present in total?
In $3\text{Ca}(\text{OH})_2$, how many oxygen atoms are present in total?
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$6\text{ O atoms}$. 3 × 2 × 1 = 6 oxygen atoms from the hydroxide groups.
$6\text{ O atoms}$. 3 × 2 × 1 = 6 oxygen atoms from the hydroxide groups.
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In $4\text{Fe}(\text{NO}_3)_2$, how many nitrogen atoms are present in total?
In $4\text{Fe}(\text{NO}_3)_2$, how many nitrogen atoms are present in total?
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$8\text{ N atoms}$. 4 × 2 × 1 = 8 nitrogen atoms from the nitrate ions.
$8\text{ N atoms}$. 4 × 2 × 1 = 8 nitrogen atoms from the nitrate ions.
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In $2(\text{NH}_4)_3\text{PO}_4$, how many hydrogen atoms are present in total?
In $2(\text{NH}_4)_3\text{PO}_4$, how many hydrogen atoms are present in total?
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$24\text{ H atoms}$. 2 × 3 × 4 = 24 hydrogen atoms from the ammonium ions.
$24\text{ H atoms}$. 2 × 3 × 4 = 24 hydrogen atoms from the ammonium ions.
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When a polyatomic ion appears unchanged on both sides, what is the preferred balancing approach?
When a polyatomic ion appears unchanged on both sides, what is the preferred balancing approach?
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Balance the polyatomic ion as a unit. Treat polyatomic ions as single units when possible.
Balance the polyatomic ion as a unit. Treat polyatomic ions as single units when possible.
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What is the final step after balancing coefficients in an equation?
What is the final step after balancing coefficients in an equation?
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Reduce coefficients to the lowest whole-number ratio. Divide all coefficients by their greatest common factor.
Reduce coefficients to the lowest whole-number ratio. Divide all coefficients by their greatest common factor.
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What kind of numbers should coefficients be in a balanced equation for typical high school problems?
What kind of numbers should coefficients be in a balanced equation for typical high school problems?
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Smallest set of whole numbers. Use the simplest ratio of positive integers.
Smallest set of whole numbers. Use the simplest ratio of positive integers.
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Identify the coefficient needed to balance: $\text{H}_2 + \text{O}_2 \rightarrow \text{H}_2\text{O}$.
Identify the coefficient needed to balance: $\text{H}_2 + \text{O}_2 \rightarrow \text{H}_2\text{O}$.
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$2\text{H}_2 + \text{O}_2 \rightarrow 2\text{H}_2\text{O}$. Need 2 $\text{H}_2$ molecules to balance 4 H atoms.
$2\text{H}_2 + \text{O}_2 \rightarrow 2\text{H}_2\text{O}$. Need 2 $\text{H}_2$ molecules to balance 4 H atoms.
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Identify the balanced form of: $\text{N}_2 + \text{H}_2 \rightarrow \text{NH}_3$.
Identify the balanced form of: $\text{N}_2 + \text{H}_2 \rightarrow \text{NH}_3$.
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$\text{N}_2 + 3\text{H}_2 \rightarrow 2\text{NH}_3$. Balance nitrogen first, then hydrogen with coefficient 3.
$\text{N}_2 + 3\text{H}_2 \rightarrow 2\text{NH}_3$. Balance nitrogen first, then hydrogen with coefficient 3.
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Identify the balanced form of: $\text{Na} + \text{Cl}_2 \rightarrow \text{NaCl}$.
Identify the balanced form of: $\text{Na} + \text{Cl}_2 \rightarrow \text{NaCl}$.
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$2\text{Na} + \text{Cl}_2 \rightarrow 2\text{NaCl}$. Need 2 Na atoms to match 2 Cl atoms.
$2\text{Na} + \text{Cl}_2 \rightarrow 2\text{NaCl}$. Need 2 Na atoms to match 2 Cl atoms.
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Identify the balanced form of: $\text{Mg} + \text{O}_2 \rightarrow \text{MgO}$.
Identify the balanced form of: $\text{Mg} + \text{O}_2 \rightarrow \text{MgO}$.
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$2\text{Mg} + \text{O}_2 \rightarrow 2\text{MgO}$. Need 2 Mg atoms to match 2 O atoms.
$2\text{Mg} + \text{O}_2 \rightarrow 2\text{MgO}$. Need 2 Mg atoms to match 2 O atoms.
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Identify the balanced form of: $\text{Al} + \text{O}_2 \rightarrow \text{Al}_2\text{O}_3$.
Identify the balanced form of: $\text{Al} + \text{O}_2 \rightarrow \text{Al}_2\text{O}_3$.
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$4\text{Al} + 3\text{O}_2 \rightarrow 2\text{Al}_2\text{O}_3$. Balance Al first (coefficient 4), then O atoms.
$4\text{Al} + 3\text{O}_2 \rightarrow 2\text{Al}_2\text{O}_3$. Balance Al first (coefficient 4), then O atoms.
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Identify the balanced form of: $\text{Fe} + \text{O}_2 \rightarrow \text{Fe}_2\text{O}_3$.
Identify the balanced form of: $\text{Fe} + \text{O}_2 \rightarrow \text{Fe}_2\text{O}_3$.
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$4\text{Fe} + 3\text{O}_2 \rightarrow 2\text{Fe}_2\text{O}_3$. Need 4 Fe atoms to make 2 $\text{Fe}_2\text{O}_3$ units.
$4\text{Fe} + 3\text{O}_2 \rightarrow 2\text{Fe}_2\text{O}_3$. Need 4 Fe atoms to make 2 $\text{Fe}_2\text{O}_3$ units.
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Identify the balanced form of: $\text{KClO}_3 \rightarrow \text{KCl} + \text{O}_2$.
Identify the balanced form of: $\text{KClO}_3 \rightarrow \text{KCl} + \text{O}_2$.
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$2\text{KClO}_3 \rightarrow 2\text{KCl} + 3\text{O}_2$. Need 3 $\text{O}_2$ molecules to provide 6 O atoms.
$2\text{KClO}_3 \rightarrow 2\text{KCl} + 3\text{O}_2$. Need 3 $\text{O}_2$ molecules to provide 6 O atoms.
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Identify the balanced form of: $\text{CaCO}_3 \rightarrow \text{CaO} + \text{CO}_2$.
Identify the balanced form of: $\text{CaCO}_3 \rightarrow \text{CaO} + \text{CO}_2$.
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$\text{CaCO}_3 \rightarrow \text{CaO} + \text{CO}_2$. Already balanced with 1:1:1 stoichiometry.
$\text{CaCO}_3 \rightarrow \text{CaO} + \text{CO}_2$. Already balanced with 1:1:1 stoichiometry.
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Identify the balanced form of: $\text{H}_2\text{O}_2 \rightarrow \text{H}_2\text{O} + \text{O}_2$.
Identify the balanced form of: $\text{H}_2\text{O}_2 \rightarrow \text{H}_2\text{O} + \text{O}_2$.
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$2\text{H}_2\text{O}_2 \rightarrow 2\text{H}_2\text{O} + \text{O}_2$. Need coefficient 2 to balance oxygen atoms.
$2\text{H}_2\text{O}_2 \rightarrow 2\text{H}_2\text{O} + \text{O}_2$. Need coefficient 2 to balance oxygen atoms.
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Identify the balanced form of: $\text{CH}_4 + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}$.
Identify the balanced form of: $\text{CH}_4 + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}$.
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$\text{CH}_4 + 2\text{O}_2 \rightarrow \text{CO}_2 + 2\text{H}_2\text{O}$. Balance carbon first, then hydrogen, oxygen last.
$\text{CH}_4 + 2\text{O}_2 \rightarrow \text{CO}_2 + 2\text{H}_2\text{O}$. Balance carbon first, then hydrogen, oxygen last.
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Identify the balanced form of: $\text{C}_3\text{H}_8 + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}$.
Identify the balanced form of: $\text{C}_3\text{H}_8 + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}$.
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$\text{C}_3\text{H}_8 + 5\text{O}_2 \rightarrow 3\text{CO}_2 + 4\text{H}_2\text{O}$. Balance 3 C atoms, then 8 H atoms, then O atoms.
$\text{C}_3\text{H}_8 + 5\text{O}_2 \rightarrow 3\text{CO}_2 + 4\text{H}_2\text{O}$. Balance 3 C atoms, then 8 H atoms, then O atoms.
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Identify the balanced form of: $\text{C}_2\text{H}_6 + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}$.
Identify the balanced form of: $\text{C}_2\text{H}_6 + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}$.
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$2\text{C}_2\text{H}_6 + 7\text{O}_2 \rightarrow 4\text{CO}_2 + 6\text{H}_2\text{O}$. Need 7 $\text{O}_2$ molecules for complete combustion.
$2\text{C}_2\text{H}_6 + 7\text{O}_2 \rightarrow 4\text{CO}_2 + 6\text{H}_2\text{O}$. Need 7 $\text{O}_2$ molecules for complete combustion.
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Identify the balanced form of: $\text{Fe}_2\text{O}_3 + \text{CO} \rightarrow \text{Fe} + \text{CO}_2$.
Identify the balanced form of: $\text{Fe}_2\text{O}_3 + \text{CO} \rightarrow \text{Fe} + \text{CO}_2$.
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$\text{Fe}_2\text{O}_3 + 3\text{CO} \rightarrow 2\text{Fe} + 3\text{CO}_2$. Reduction reaction: Fe₂O₃ reduced by CO.
$\text{Fe}_2\text{O}_3 + 3\text{CO} \rightarrow 2\text{Fe} + 3\text{CO}_2$. Reduction reaction: Fe₂O₃ reduced by CO.
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Identify the balanced form of: $\text{C}_2\text{H}_5\text{OH} + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}$.
Identify the balanced form of: $\text{C}_2\text{H}_5\text{OH} + \text{O}_2 \rightarrow \text{CO}_2 + \text{H}_2\text{O}$.
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$\text{C}_2\text{H}_5\text{OH} + 3\text{O}_2 \rightarrow 2\text{CO}_2 + 3\text{H}_2\text{O}$. Balance 2 C atoms, then 6 H atoms, then O atoms.
$\text{C}_2\text{H}_5\text{OH} + 3\text{O}_2 \rightarrow 2\text{CO}_2 + 3\text{H}_2\text{O}$. Balance 2 C atoms, then 6 H atoms, then O atoms.
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Identify the balanced form of: $\text{Fe} + \text{HCl} \rightarrow \text{FeCl}_2 + \text{H}_2$.
Identify the balanced form of: $\text{Fe} + \text{HCl} \rightarrow \text{FeCl}_2 + \text{H}_2$.
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$\text{Fe} + 2\text{HCl} \rightarrow \text{FeCl}_2 + \text{H}_2$. Need 2 HCl molecules to provide 2 Cl atoms.
$\text{Fe} + 2\text{HCl} \rightarrow \text{FeCl}_2 + \text{H}_2$. Need 2 HCl molecules to provide 2 Cl atoms.
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