The science that tries to understand how matter behaves by studying how atoms and molecules behave.
What is needed in the study of biology and physics?
Chemistry, the central science.
Anything that occupies space and weighs something ("stuff").
What are properties in Chemistry?
The characteristics that give a specific type of matter its unique identity.
Water freezes at 32 F, and boils at 212 F (at sea level). These are examples of ________ of water.
A form of matter that has a definite composition and distinct properties.
The types and amounts of simpler substances in a sample.
Water is always 1/9 hydrogen by mass and 8/9 oxygen by mass. This is an example of what?
A substance, (water), specifically the composition of water.
What is an example of a substance that is composed of only one kind of atom?
What is a name for a substance that is composed of only one kind of atom?
What is the smallest possible piece of aluminum that can exist?
An aluminum atom.
What is the smallest possible piece of any element that can exist?
An atom of said element. An <insert element name> atom.
What is air on Earth primarily composed of?
Oxygen and Nitrogen
Elements have what that make them distinctly different from other elements?
A sample of pure oxygen can be subdivided until the smallest possible sample of oxygen remains that has what?
Properties of pure oxygen.
What is the smallest possible sample of oxygen?
A molecule of oxygen.
Splitting a molecule of oxygen gas gives two particles with properties other than those of oxygen gas. What are these two particles called?
Atoms of Oxygen.
Definition of diatomic.
Molecules that are composed of only two atoms.
Are the Oxygen molecules that we breathe diatomic or triatomic?
Are Hydrogen gas molecules diatomic or triatomic?
Are ozone molecules diatomic or triatomic?
True or False: Ozone has different properties from those of diatomic oxygen.
Definition of triatomic.
Molecules that are composed of three atoms.
True or False: Ozone and the air we breath are both forms of the element Oxygen.
True or False: Ozone and air both consist of Oxygen thus both are breathable by humans.
True or False: Atoms are easily split into smaller particles.
If one molecule of O2 reacts with two molecules of H2 then how many molecules of what form?
Two molecules of H2O
True or False: H2O (water) has properties that are similar to those of O2 and H2.
False. They are very different.
A chemical reaction is the same thing as...
A chemical change
If one molecule of O2 reacts with two molecules of H2, two molecules of H2O form. What took place?
A chemical reaction A.K.A. a chemical change.
What is the chemical equation that represents one O2 molecule reacting with two H2 molecules?
2H2 + O2 = 2H2O
Chemistry is a(n) __________ science.
What is the first step in the scientific method?
Make observations and recognize patterns.
In the first step of the scientific method, if the same observation applies to many different situations, it is called a(n) ______ if it can be quantified.
What is the second step of the scientific method?
Develop an idea - called a hypothesis - which explains the patterns.
In the scientific method, a hypothesis should have ________ value and be testable experimentally.
In the scientific method, a hypothesis should be as __________ as possible.
relating to, measuring, or measured by the quantity of something rather than its quality.
refers to a type of information based in quantities or else quantifiable data (objective properties) —as opposed to qualitative information which deals with apparent qualities (subjective properties). It may also refer to mass, time, or productivity.
What is the third step of the scientific method?
Design and carry out experiments that test the validity of the hypothesis (i.e. to see if the results of the experiment conform to the predictions).
In the scientific method, if the hypothesis correctly predicts the outcome of these experiments, it is called a ______, or ______.
theory or model
What is the difference between a law and a theory?
A law summarizes what happens, a theory tries to explain why it happens.
What is the Law of Conservation of Mass?
Any system closed to all transfers of matter and energy (both of which have mass), the mass of the system must remain constant over time, as system mass cannot change quantity if it is not added or removed.
Mass can neither be created nor destroyed, although it can be rearranged in space and entities associated with it may change in form.
The law implies (requires) that during any chemical reaction, nuclear reaction, or radioactive decay in an isolated system, the total mass of the reactants or starting materials must be equal to the mass of the products.
All matter is composed of small, indestructible particles called _______.
The Law of Convservation of Mass was formulated by whom and when?
Antoine Lavoisier, 1789
Atomic theory was officially formulated by whom?
What is atomic theory?
Each chemical element is composed of atoms of a single, unique type, and though they cannot be altered or destroyed by chemical means, they can combine to form more complex structures (chemical compounds).
Atoms of one substance can or cannot be changed into atoms of another substance?
Cannot: atomic theory, John Dalton.
Describe the findings in Antoine Lavoisier's Law of Conservation of Mass.
No mass is created, nor destroyed in chemical reactions.
Give an example of the Law of Conservation of Mass.
4 pounds of hydrogen gas reacts with 32 pounds of oxygen gas to form 36 pounds of water vapor, no more, no less.
4 lb + 32 lb = 36 lb
If the mass of one of the substances in a chemical reaction is missing, it can be found through ________.
A second example of Law of Conservation of Mass: How many grams of carbon react with 32 grams of oxygen to form 44 grams of carbon dioxide if carbon dioxide is the only product?