quiz 5 Flashcards
carbonic acid immediately decomposes to produce…
H2CO3 (aq) -> H20 (L) + CO2 (g)
sulfurous acid immediately decomposes to produce…
H2SO3 (aq) -> H20 (L) + SO2 (g)
ammonium hydroxide immediately decomposes to produce…
NH4OH (aq) -> H2O (L) + NH3 (g)
ammonium sulfide immediately decomposes to produce…
(NH4)2S (aq) -> H2S (g) + 2NH3 (g)
when is activity taken into account for a chemical reaction
when determining whether a metal will displace another metal (single displacement). in order to do so, the metal must be more active than the metal it is displacing.
a reaction occurs in a double displacement if…
- a precipitate is formed through the formation of an insoluble substance
- H2O (L) is formed through an acid-base reaction
- gas is formed through decomposition
what makes a solution a good conductor of electricity
dissolved ions must be present to make it a conductor of electricity. a good conductor of electricity is called and electrolyte
polar compounds
have both a partial positive and partial negative charge.. an example of this is water
signs of a chemical change
- color change
- production of an odor (g)
- change of temperature
- evolution of a gas (formation of bubbles)
- precipitate
solute
substance being dissolved
solvent
substance doing the dissolving
melting
process by which pos and neg charges are separated w/o solvent present
acid-base reaction
- contains an acid (H___) and base (typically ___OH, though it can be a carbonate, sulfide, or sulfite as well) and forms H20 (or S20)
- always exothermic
- always double displacement
precipitation reactions
always double displacement reactions. when a solid is formed
redox reactions
- when a compound reacts with oxygen or when the charge of an atom changes during reaction.
- all single displacements are redox
- the O2 or substance with the charge is the oxidant, while the substance without the charge is the reductant
when the sign of ∆H is negative
- the reaction is exothermic
- kJ is on the products side
- reaction feels hot
- reactants themselves contain energy than the products (through the law of conservation of energy, both sides must be equal, therefor the energy produced in the reaction was previously contained in the reactants)
when ∆H is positive
- the reaction is endothermic
- kJ is a reactant
- energy is being absorbed and the reaction feels cool
- reactants have less energy than products
empirical formula
- most simplified version of the molecular formula (true formula)
- n*empirical formula=molecular formula
gas evolution reactions
-an aqueous reaction where gas is formed