Chemical reaction Review
What components are necessary to create the chemical reaction necessary to shoot off a rocket?
fuel and oxygen
Analyze the compound NaC2H3O2 to identify the kinds of atoms and the total number of atoms involved
Na = sodium (1); C = carbon (2); H = hydrogen (3); O = oxygen(2)
Define endothermic
When an heat is absorbed
Define exothermic
When heat is released
What is the chemical equation for the chemical reaction between hydrogen peroxide and sunlight? What type of chemical reaction is this and why?
2H2O2 → O2 + 2H2O --- this is a decomposition because the hydrogen peroxide is broken down into separate water and oxygen molecules
In a chemical reaction, how do the atoms in the new substance compare to the atoms in the old substance?
they are the same atoms, just rearranged
Define synthesis (provide the simple equation)
two reactants create one product A + B → AB
Define double replacement (provide the simple equation)
when compounds react to form two new compounds AB + CD → AC + BD
What is a balanced equation?
when the number and type of atoms are the same on both sides of the reaction
Define Chemical reactions
A chemical reaction are changes that occur when two atoms,ions or molecules interact
Satisfy the following equations according to the Law of Conservation of Mass and identify what type of chemical reaction they are: AlBr3 + K → KBr + Al b. CaF2 + Li2SO4 → CaSO4 + LiF
AlBr3 + 3K → 3KBr + Al CaF2 + Li2SO4 → CaSO4 + 2LiF Single Replacement DoubleReplacement
What happens to energy during a chemical reaction?
Energy is released
How does physical changes differ from a physical change?
a chemical change will completely change the substance by rearranging the atoms, we cannot get the original substance back; a physical change does not change the substance and we can get the original substance back
Define conservation of mass
a reaction does not create or destroy atoms; the total mass stays the same from beginning to end
Define closed system
a reaction where nothing is added or allowed to escape from the system
Define open system
a reaction where something could be added or something could escape
What are the physical properties of matter?
color, density, solubility, conductivity
What is the chemical reaction for rust (identify reactants & products)?
iron + oxygen → iron oxide
In the oxygen formation lab, would the wooden split reignite in the absence of oxygen? Why or why not?
no → fire needs oxygen, heat, and a material
Define single replacement (provide the simple equation)
one element replaces another AB + C → AC + B
Define decomposition (provide the simple equation)
one reactant breaks down into two or more substances AB → A + B
What are the chemical properties of matter?
production of gas bubbles, temperature changes, the production of light, a change in odor
What are some examples of evidence that you can collect to prove a chemical change has occurred?
production of gas or precipitate, change in color, expanding of a bag
Define products
the ending substances of a chemical reaction
What caused the wooden split to reignite during the oxygen formation lab?
the formation of oxygen from the reaction
Define coefficient
the number in front of the element or compounds; tells you how many atoms or molecules you have
After a chemical reaction, how do new substances differ from the old substances?
the properties of the new substances are different than the original
What gives new substances new properties?
the rearrangement of the atoms into a new substance gives the new properties
Define reactants
the starting substances in a chemical reaction
