Atomic Structure
An atom of chlorine has 7 valence electrons. Aluminum, on the other hand, has 3 valence electrons.
Chemical Reactions
Reaction rate refers to the decrease in concentration of reactants or the increase in concentration of
products over time. An increase in temperature can speed up a reaction by increasing kinetic energy,
causing molecules to move faster and collide more frequently.
Surface Area and Reaction Rate
Increasing surface area can enhance reaction rate by providing more points of contact for reactant
molecules. A catalyst can speed up a chemical reaction by providing an alternate pathway with lower
activation energy.
Equilibrium and Energy
Equilibrium occurs when the rates of forward and reverse reactions are equal. An endothermic reaction
absorbs energy, while an exothermic reaction releases energy.
Heat Transfer and Specific Heat Capacity
When a flask feels hot after being touched, it is an exothermic process. Specific heat capacity is the
amount of heat required to raise 1 gram of a substance by 1 degree Celsius.
Acids and Bases
, A hydrogen ion donor is called an acid, while a hydrogen ion acceptor is called a base. A base can make a
substance feel slippery or taste bitter. Acidic substances typically have a pH below 7, while basic
substances have a pH above 7.
Neutralization
Neutralization occurs when an acid reacts with a base to form water and a salt. Soap, being a base, can
neutralize acidic substances.
Lemonade; acid or base? ✅Acid (tastes sour)
Define solute. ✅The part of the solution in less amount.
Define solvent. ✅The part of the solution in greater amount. (HINT: solvent is a bigger word than
solute)
How many atoms are in 1 mole? ✅1 mole = 6.02 x 10^23 atoms/molecules
What is the volume occupied by 1 mole of a gas at STP? ✅1 mole of gas at STP = 22.4 L
Define STP. ✅Pressure = 1 atm or 101.3 kPa
Temperature = 0 degrees Celsius or 273 K
What is the temperature at absolute zero? ✅0 K (all molecular motion stops)
What causes gas pressure? ✅Gas molecules are constant motion and collide with the walls of their
containers and with the surfaces that they come into contact with. This collision causes pressure.
Equal volumes of gases at STP have equal _____. ✅Moles.