Back to Basics
the study of matter and the changes it undergoes
Chemistry
What units are used when you calculate molar mass?
g/mol
Periodic table is organized by increasing..?
atomic number (#protons)
Balance the following equation:
___H2O --> ___H2 + ___O2
2 H2O --> 2 H2 + 1 O2
What is the formula and units for pressure?
Pressure = force/area
units are N/m^2
Anything that has mass and volume (takes up space)
Matter
What are the units used for atom's masses?
Atomic mass units (amu)
Electrons during oxidation and reduction (redox)
LEO GER
Lose electrons oxidation
Gain electron reduction
Balance the following equation:
___N2 + ___H2 --> ___NH3
1 N2 + 3 H2 --> 2 NH3
What unit do we always use for temperature when doing gas law calculations?
Kelvin
2 or more elements that are chemically combined, that cannot be easily separated into their elements.
Compound
Steps to calculate molar mass (Ex: H20)
Use your periodic table to find the atomic masses of Hydrogen and Oxygen. Hydrogen's atomic mass gets multiplied by 2 because of the subscript 2 next to it. Then you add the doubled Hydrogen and Oxygen atomic masses together.
___ are less than 7 on the pH scale, while ____ are greater than 7
Acids < 7
Bases > 7
You cannot change these when balancing equations
Subscripts
Boyle's Law - what is the relationship between pressure and volume?
Inversely proportional - as one increases the other decreases
As volume decreases, pressure increases
Ex: syringe
Give an example of a physical AND a chemical change
Mixtures, change in state (s,l,g)
Chemical:
Burning, Rusting, Digestion, Rotting
What is Avogadro's Number?
6.022 x 10^23
What is it called when you mix an acid and a base and what is produced?
Neutralization reaction
Salt and h20
Law of conservation of mass
In a chemical reaction. matter is neither created or destroyed (In other words, the number and type of atoms going INTO a reaction MUST be the same as the number and type of atoms coming OUT)
Charles Law - what is the relationship between temperature and volume?
Direct relationship
As one increases, the other also increases.
EX: Temp increase, volume increase
Name the 3 subatomic particles and their properties:
Charge
Location
Effects on charge OR mass
If you change the number of them, what is created in a certain atom?
Proton: Positive, nucleus, cannot be changed, effect on mass, effect on charge
Neutron: Neutral, nucleus, effect on mass, # can be changed and creates isotopes
Electrons: Negative, outside nucleus, effect on charge, # can be changed and creates ions
What is the set-up for finding percent composition? (EX: finding percent of C in C02).
Percent comp by mass = mass of given element C / total mass of compound.
then multiply that number by 100 to get the percent.
Physical properties of metals
Luster
Ductile
Malleable
Conductors
High density
Balance the following equation:
___H2SiCl2 + ___H2O → ___H8Si4O4 + ___HCl
4 H2SiCl2 + 4 H2O → 1 H8Si4O4 + 8 HCl
Gay Lussac's Law - what is the relationship between pressure and temperature?
As temp increases, pressure increases