Section 3.1 Q-cards Flashcards
Chemical reaction
A process in which substances interact to form one or more different substances.
Reactant
A starting substance in a chemical reaction
Product
A end result in a chemical reaction
When do chemical reactions occur?
Chemical reactions occur when bonds between the outer parts of atoms are formed or broken.
What happens in a chemical reaction?
Chemical reactions involve
changes in matter
making of new materials with new properties
energy changes.
What do Symbols, Formulas, and Chemical equations describe?
Symbols represent elements
Formulas describe compounds
Chemical equations describe a chemical reaction.
Chemical Equation
A condensed statement that expresses chemical change using symbols and chemical names or formulas.
Chemical equations show the conversion of reactants (the molecules shown on the left of the arrow) into products(the molecules shown on the right of the arrow).
What dose a + sign represent?
A “+” sign separates molecules on the same side.
What dose the arrow represent?
The arrow stands for yields or reacts to produce
What dose this represent
(⇌)
This represents a reversible reaction
What is the law of conservation of mass?
mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations.
What are the three forms of a chemical equation
Skeleton
Word
Balenced
What is a word equation?
In a word equation, the reactants and products are identified by their names only.
For example
Magnesium + oxygen → Magnesium oxide
What is a Skeleton equation?
A skeleton equation is an unbalanced equation that does not follow the Coservation of Mass.
The number of atoms on the left side (reactants) of the chemical equation does not equal the number of atoms on the right side (Products).
Example
H2(g)+Cl2(g) —> HCl2(g)
What is a Balenced equation?
The equation that follows the Law of Conservation of Mass.
The number of atoms on the reactant side equals the atoms on the product side.
In most chemical equations, numbers placed in front of the elements or compounds (coefficients) are required to balance the equation.
Word balanced equation?
- Moles
- 3 moles or the symbols used in the balanced equation
