Synthesis
What happens in a synthesis reaction?
In a synthesis reaction, two or more reactants combine to produce a single product.
What happens in a single replacement reaction?
In a single replacement reaction, a reactive element and a compound react to produce another element and another compound.
What happens in a double replacement reaction, and what happens in a neutralization reaction?
In a double replacement reaction, two ionic solutions react to produce one ionic solution and one ionic solid.
What happens in a combustion reaction?
A rapid reaction with a hydrocarbon with oxygen
How do you define a physical change? Give 2 examples.
A substance goes through a change without changing its composition (molecules its made of).
Examples: cutting paper, boiling water, etc.
How do you represent a synthesis reaction in the form of an equation?
element + element → compound A + B → AB (The letters A and B represent elements.)
How do you represent a combustion reaction in the form of an equation?
hydrocarbon + oxygen → carbon dioxide + water CxHy + O2 → CO2 + 2H2O (The subscripts x and y represent integers.)
How do you define a chemical change? Give 2 examples.
A change where new substances are formed.
Examples: Metal rusting, burning wood, etc
Complete the following reaction and balance it:
Mg(s) + Cl2(g) ->
Mg(s) + Cl2(g) -> MgCl2(aq)
Write a skeleton decomposition reaction for the compound LiBr.
LiBr(aq) --> Li(s) + Br2(l)
Complete the following reaction and balance it:
Cl2(g) + Na2O -->
2Cl2(g) + 2Na2O --> O2(g) + 4NaCl(aq)
Complete the following skeleton reaction:
NaOH(aq) + FeCl3(aq) -->
NaOH(aq) + FeCl3(aq) --> NaCl(aq) + Fe(OH)3(s)
How do you recognize a combustion reaction?
Products will always be CO2(g) and H2O(g).
OR
Reactants will always be a hydrocarbon and oxygen.
(Answers can vary)
Part 1: What is an indication of an exothermic reaction? Give an example.
Part 2: How do you define an endothermic reaction?
Part 1: It feels hot. Example: Burning wood to make a campfire.
Part 2: A reaction where heat is absorbed from surroundings.
Write the following reaction as a balanced chemical equation:
Barium reacts with phosphorus to form barium phosphide.
6Ba(s) + P4(s) --> 2Ba3P2
Answer the following reaction and balance the whole reaction correctly: WP2 -> ?
2WP2 -> 2W(s) + P4(s)
Write the following reaction as a balanced chemical equation:
Aluminum metal mixes with sulfuric acid and makes alumnium sulfate and hydrogen gas.
2Al(s) + 3H2SO4(aq) --> Al2(SO4)3(aq) + 3H2(g)
What is one way to recognize a double replacement reaction?
What is a "trick" you can use to make sure you have correctly balanced a combustion reaction?
Make sure the coefficient for the hydrocarbon is either 1 or 2.
What are the 5 observations of a chemical change?
1. Change in odour.
2. Change in energy.
3. Change in colour.
4. Formation of gas.
5. Formation of precipitate.
Write the complete chemical equation for the following:
A piece of magnesium reacts with oxygen.
Mg(s) + O2(g) --> MgO
Write the balanced chemical equation for the process of hydrolysis where water splits into its elements.
2H2O(l) --> 2H2(g) + O2(g)
Write the following chemical equation as a word equation with states:
2KBr(aq) + Cl2(g) --> 2KCl(aq) + Br2(l)
Aqueous potassium bromide reacts with chlorine gas to form aqueous potassium chloride and liquid bromine.
Write the following word equation as a balanced chemical equation:
Barium nitrate is mixed with sodium sulfate.
Ba(NO3)2(aq) + Na2SO4(aq) --> BaSO4(s) + 2NaNO3(aq)
Write the following as a balanced chemical equation:
The ethanol in a lamp burns.
C2H5OH(l) + 3O2(g) --> CO2(g) + 3H2O(g)
Part 1: What is the Law of Conservation of Mass?
Part 2: How do we observe the Law of Conservation of Mass in chemical equations?
Part 1: Total number of atoms/ions in the reactants is equal to the total number of atoms/ions in the products.
Part 2: We balance chemical equations.