Module Three - Chemical Reactions Flashcards
What is Avogadro’s number?
6.022xE23
Aqueous (aq) mean that…
we have a substance thats dissolved in water.
Solution are defined as…
a uniform mixture of two or more pure substances.
What are precipitation reactions?
When two aqueous solutions are mixed to form an insoluble product. A precipitate forms if either of the two reactants are insoluble. If both possible products are soluble, no reaction occurs (like with cacl2 and kno3).
What is the solubility pattern for NH4+ and alkali metal ions?
They are always soluble.
Whats the solubility pattern for CH3COO- and NO3-?
They are always soluble.
Whats the solubility pattern for Br-. Cl-, and I-?
Always soluble except, Ag+, Hb2+, and Pb2+.
Whats the solubility pattern for CO32- and PO43-?
Usually insoluble.
What is an electrolyte?
Any substance that produces an electrically conducting solution when dissolved in a polar solvent, such as water.
What is an acid-base reaction?
When a proton (a hydrogen ion, H+) is transferred from one chemical to another.
What is an acid?
A chemical that produces H3O+ and an anion when dissolved in water. Acids are the proton donors. (For example, HCL produces H3O+ and Cl-).
What is a base?
A chemical that generates OH- and a cation. Bases are the proton acceptors. (NH3 makes OH- and NH4+ in water)
What is the difference between strong and weak acids?
Strong acids completely ionize in water. HCL is a strong acid, and after reacting, essentially no HCL molecules remain in the water.
What are the six strong acids?
HCl, HBr, HI, H2SO4, HNO3, and HClO4.
What are the six strong bases?
LiOH, NaOH, KOH, Ca(OH)2, Sr(OH)2, and Ba(OH)2.
What are the three weak acids?
CH3COOH, H2CO3, and H3PO4.
What is the one weak base?
NH3.
What is a neutralization reaction?
A special kind of acid-base reaction, that results in a salt and H2O.
What is a gas-forming reaction?
When a solid alkali metal is added to water OR when an acid is added to solid metal, the products are aqueous salt, hydrogen gas, and energy.
What is the gas-forming rule with metal carbonates and acid?
Metal carbonates and acid react to form aqueous salt, water, and carbon dioxide gas.
What is the gas-forming rule with metal sulfites and acid?
Metal sulfites and acid react to form aqueous salt, water, and sulfur dioxide gas.
What is the gas-forming rule with metal sulfides and acid?
Metal sulfides and acid react to form aqueous salt and hydrogen sulfide gas. Notice how this one doesnt have water as a product!
What does it mean when we write NaCl(aq)?
The solution contains aqueous sodium ions and aqueous chloride ions freely moving in the solution.
What is the difference between strong and weak electrolytes?
A strong electrolyte is a compound that completely dissociates into ions when it is in an aqueous solution. Weak ones dissociate only partially.
Why do ionic compounds conduct electricity when dissolved in solution?
Because their cations and anions can move freely in the solution.
What is a spectator ion?
Any ion present in the but not involved directly in a reaction.
What is a net ionic equation?
An equation that includes only the symbols or formulas of ions or molecules.
What does Q1 and Q2 stand for?
Q1 is the charge on the cation and Q2 is the charge on the anion. D stands for the distance between the atoms in pm.
What is the difference between ionic and covalent compounds?
Ionic compounds completely transfer electrons whereas covalent compounds share them.
What are the Ox-Redox rules?
Atoms in a pure elemt have the ox number of 0.
Monatomic ions have the ox number equal to the charge.
When with another element, F always has the ox number of -1.
The ox number of H is +1 in most compounds, but is -1 with alkali metals.
Oxygen is -2, except when with fluorine (-1) or in peroxides (-1).
Cl, Br, and I are -1 when with O or F.
What is an oxidation-reduction reaction?
When electrons are transferred from one reactant atom, molecule, or ion to another.
What is the difference between oxidation and reduction?
Oxidation loses electrons, whereas redox gains them.
Why do salts dissolve in water?
Because solvation energy, or ion-water attractions, are stronger than lattice attractions, or the ion-ion attractions that keep them together. The more the strength of lattice attractions, the more likely they are to be insoluble.
What is the difference between H3O+ and H+?
Nothing. They’re the same thing.
