Balancing and 5 Types of Chemical Reactions

Balancing and 5 Types of Chemical Reactions

Law of Conservation of Matter

Law of Conservation of Matter (or Mass)

• According to the Law of Conservation Matter, matter cannot be created or destroyed,

• which means the amount of reactants (grams and atoms) is equal to the amount of products (grams and atoms).

Multiple Select

What is conserved in a chemical reaction?

• atoms

• molecules

• grams

• coefficients

Multiple Choice

Mass of reactants equals...

• mass of the all atoms

• mass of the products

• 0 grams

Open Ended

If the reactants are 50 gram, how many grams

Multiple Choice

What is the Law of Conservation of mass?

• Mass is created in a chemical reaction
• Mass is created in a physical change
• New chemicals formed from a chemical reaction have a larger overall mass than the original reactants
• Mass is never created or destroyed

Vocabulary

►Chemical Equation: A representation of a chemical reaction using the formulas of the starting substances that react and the new substances that are formed

►Reactants: the starting substances that enter into a chemical reaction (left side of the reaction arrow)

►Products: the new substances formed during a chemical reaction (right side of the reaction arrow)

►-->: yields or a reaction arrow; separates reactants and products

►Coefficients: Number in front of a substance; apply to all elements in compound/molecule

►Subscripts: number after an element; applies to only one element

►(g), (l), (s): gas, liquid or solid

►(aq): aqueous (dissolved in water)

Multiple Choice

Look at the chemical reaction: 4 P + 5 O₂ → P₂O₅. Does it obey the law of conservation of mass?

• yes, it is properly balanced

• no, you need more phosphorus atoms on the reactant side

• no, you need more oxygen atoms on the product side

• no, you need more phosphorus and oxygen atoms on the product side

Multiple Choice

a substance that is formed as the result of a chemical reaction

• Product 
• Reactant
• Starters
• Enders

Multiple Choice

the starting materials in a chemical reaction

• Products
• Reactants
• Starters
• Enders

Multiple Choice

What are Chemical Reactions?

• It's when you mix substances.
• a process in which atoms rearrange to form new substances
• When something bubbles.
• letter and numbers showing the types and number of atoms

Multiple Choice

What is the arrow in a chemical equation...
H_{2 +} O --> H₂O

• Reactants
• Products 
• Yields 
• Chemical Equation 

Multiple Choice

Which of the following is a common sign that a chemical change has occurred?

• A chemical has turned a different color, bubbled, and/or changed temperature.

• A chemical has changed to a different state of matter, such as a liquid to a solid.

• A chemical has changed size.

• A chemical has become a different shape.

Multiple Choice

When balancing equations, the rule is that you can only add, change, and remove

• Coefficients
• Mass
• Subscripts
• Elements 

Multiple Choice

The number of atoms you begin with in a chemical reaction ...

• must be the same as the number of  atoms you end with
• must be an even number
• can be different to the number you finish with
• changes depending on how much energy is formed

Multiple Choice

In a chemical reaction, everything to the rightof the arrow is called ______________.

• Products
• Yields
• Molecules
• Reactants

Multiple Choice

The substances at the beginning of a chemical equation are called the ____

• product
• yield
• chemical symbol
• reactants

Multiple Choice

The blue numbers in the image below represent ________

• I don't know, and don't want to try
• coefficients
• subscripts
• none of the answers are correct

5 Types of Chemical Reactions

►Double Displacement- occurs when two different compounds react to form two new compounds.

►Single Displacement- occurs when an uncombined element replaces an element that is part of a compound.

►Synthesis- occurs when two or more simple substances combine to form one more complex substance.

►Decomposition- occurs when one complex substance breaks down into two or more simpler substances

►Combustion- a type of double displacement reaction where a compound is reacted/burned with oxygen gas to produce carbon dioxide gas, water, and heat

Multiple Choice

Which reaction type is the following:  Na + CaF₂ --> Ca + NaF

• Decomposition
• Single Replacement
• Synthesis
• Double Replacement

Multiple Choice

Which reaction type is the following: AgF + CaCl₂ --> AgCl + CaF₂

• Decomposition
• Single Replacement
• Synthesis
• Double Replacement

Multiple Choice

Which chemical reaction breaks down into 2 substances?

• Double Replacement
• Single Replacement
• Synthesis
• Decomposition

Multiple Choice

Which chemical reaction forms Carbon Dioxide and Water?

• Double Replacement
• Single Replacement
• Combustion
• Decomposition

Multiple Choice

Identify this type of reaction,
Cl₂ + 2KI _-->  I₂ + 2KCl

• Synthesis
• Single Replacement
• Double Replacement
• Decomposition

Multiple Choice

Which of the following is an example of synthesis?

• Na + Br₂ --> NaBr
• KClO₃ --> KCl + O₂
• HgO + Cl₂-->HgCl + O₂
• Cl₂ + NaBr --> NaCl + Br₂

Multiple Choice

A + B → AB : is the general form for which reaction type?

• Double Replacement
• Synthesis
• Combustion
• Decomposition