Balancing Chemical Equations + Redox Reactions

Chemical Reactions

100

What is the Reactant of the chemical equation and where is it located?

The reactant is the original equation and it is always located on the left side of the equation.

200

What is the Product of a chemical equation and where is it located?

The product is the chemical change or new substance. It is always located on the right side of the equation.

300

Identify the reactants and products in the following chemical equation: H2 + NaCl ---> H2Na + Cl + S

Reactants: H₂ and NaCl 

Products: H₂Na, Cl, and S

400

What does the law of conservation of mass states?

The law of conservation of mass states that matter durning a chemical change can neither be created nor destroyed.

500

How many atoms does each element have in the following chemical equation: NaOH + H₂CO₃ ---> Na₂CO₃ + H₂O

Reactants - 1Na, 4O, 3H, 1C

Products - 2Na, 1C, 4O, 2H

How to Balance Equations

100

What is the first thing you should do when you have an unbalanced chemical equation?

Count the atoms of the elements in the reactants and products

200

Which part of the chemical equation are you to add or change.

The Coefficients

300

Within a chemical formula, if you don't see a subscript, you can conclude that there are how many atoms of that element within each molecule.

One

400

What is the fourth step of balancing a chemical equation (after you know the number of atoms on each side of the arrow)?

The third step is to adjust the coefficient of each molecule to balance out equally.

500

What is one reason that we balance chemical equations?

To validate that the Law of Conservation of Mass is true.

Balancing Chemical Equations

100

Balance the following equation: _____H₂ + ____O₂ ---> ____H₂O

2 H₂ + 1 O₂ ---> 2 H₂O

200

Balance the following Equation: _____KClO₃ ---> KCl + ______O₂

2KClO₃ ---> 2KCl + 3O₂

300

Balance the following equation: ____C₃H₈ + _____O₂ ---> ____CO₂ + ____H₂O

1C₃H₈ + 5O₂ ---> 3CO₂ + 4H₂O

400

Balance the following equation: ____P + _____O₂ --->_____P₂O₅

4P + 5O₂ ---> 2P₂O₅

500

Balance the following equation: ___NaBr + ____CaF₂ ---> ____NaF + ____CaBr₂

2NaBr + 1CaF₂ ---> 2NaF + 1CaBr₂

Redox Reactions

100

Name two of the five common types of chemical reactions.

synthesis, decomposition, combustion, single-replacement, or double replacement

200

True or False: Oxidation is when an atom gains electrons and reduction is when an atom loses electrons.

False. OIL RIG

300

What is the role of the reducing agent? Is it oxidized or reduced?

Reduces another substance by losing its own electrons. It is oxidized.

400

Which element is more likely to be a strong oxidation agent: Fluorine or Sodium

Fluorine because it is more electronegative

500

With the following equation:

2 Al + 2Fe + 3O₂ --> 2Fe + 2Al + 3O

identify what is oxidized and reduced. Then, identify the oxidizing agent and the reducing agent.

Aluminum: oxidized, reducing agent

Iron: reduced, oxidizing agent

Oxidation Numbers

100

What is an oxidation number?

the number of electrons lost of gained by an atom when it forms an ion (equal to its charge)

200

What does the sum of the oxidation numbers in a neutral compound equal? in a polyatomic ion?

neutral compound: 0

polyatomic ion: the charge of the ion

300

What is the oxidation number of each element in the following:

H₃PO₄

CO₃^2-

H= 1 | P= +5 | O= -2

C= +4 | O= -2

400

Find which element is being reduced and oxidized in the following equation:

Mg + Cu(NO₃)₂ --> Mg(NO₃)₂ + Cu

Reduced: Cu²⁺

Oxidized: Mg

500

Find which element is being reduced and oxidized in the following equation:

BaCl₂ + KIO₃ --> Ba(IO₃)₂ + KCl

Bonus: Balance the equation.

This is not a redox reaction.

BaCl₂ + 2 KIO₃ --> Ba(IO₃)₂ + 2 KCl