Definitions/Main Questions
What is the definition of a property of matter?
A property is a characteristic used to classify or identify matter.
What is a physical property?
Physical properties are observable (5 senses) and measurable.
What is an endothermic reaction?
A chemical reaction that absorbs heat inwards
How do you know how many elements (types of atoms) are in a chemical formula?
Count the Capitals.
What are reactants?
Before the reaction, on the left side of the equation
What can be used as evidence that a chemical reaction has occurred?
The cold, heat, light, sound, gas produced, precipitated/powder, pH change (something new)
What is a chemical property?
Chemical properties are properties with the ability to change into something new.
What is an exothermic reaction?
A chemical reaction that releases heat outwards.
What is an unbalanced chemical equation?
An equation that doesn't have the same number of atoms of each element in the products as the reactants.
Ex: N2 + H2 ---> NH3
N=2 N=1
H=2 H=3
What are products?
After the reaction/right side of the equation
Ex: reactants ----> products.
What is the difference between a chemical formula and a chemical equation?
A chemical formula has just a formula for a molecule(s) and a chemical equation has multiple molecules to yield something new.
Give an example of a physical property and a chemical property.
Physical: Color, smell/odor, hardness, texture, luster, shape, length/width, viscosity, ductility, solubility, malleability, mass, volume, density, opacity, conductivity, magnetism, change in state, freezing point, boiling point, melting point
Chemical: Reactivity, toxicity, pH acidity, tarnishing, fermenting, oxidation, flammability, radioactive, corrosive, explosive, pyrophoric.
Give the term for the following definition:
No new matter (atoms) can be either created or destroyed in a chemical reaction.
(FULL NAME)
Law of Conservation of Matter/Mass
What does yields mean?
The arrow in the middle (makes/produces)
Ex: Reactants -----> Products
What is a balanced chemical equation?
An equation that has the same number of atoms of each element in the products and reactants.
Ex: C + 2H2 ----> CH4
C=1 C=1
H=4 H=4
What is the Law of Conservation of Mass (matter)?
No new matter (atoms) can be either created or destroyed in a chemical reaction
What is a physical change?
Change looks, appearance, same substance.
What is an example of an Exothermic Reaction?
Rusting iron, burning sugar, mixing acids in water, making ice cubes.
6CO2 + 6H2O --------> C6H12O6 + 6O2
What are the reactants?
6CO2 and 6H20
6CO2 + 6H2O --------> C6H12O6 + 6O2
What are the products?
C6H12O6 + 6O2
Give the question for the following terms:
The ability to be hammered into thin sheets.
Malleability
What is a chemical change?
Produce something new.
What is an example of an Endothermic Reaction?
Baking bread/cookies, evaporating water, cooking an egg, melting ice cubes.
How do you know how many molecules there are in a chemical equation?
The coefficient.
Is the chemical equation for photosynthesis (6CO2 + 6H2O --------> C6H12O6 + 6O2) balanced or not? Why?
Yes, because the there are 6 carbons, 12 oxygens 12 hydrogens, and 6 oxygens. The product contains 6 carbons, 12 hydrogens, 6 oxygens, and 12 oxygens.