Science - Chemistry Pt.2 Flashcards
exceptions in acid
H3PO4 = phosphoric acid H3PO3 = phosphorous acid H2SO4 = sulfuric acid H2SO3 = sulfurious acid
factors influencing the rate of chemical reaction
- concentration
- surface area
- temperature
- catalyst
- type of reactant/ nature of reaction
- pressure
concentration
greater the concentration, more likely molecules to collide.
* for a solid and pure liquids, their concentrations doesn’t change
surface area
heterogeneous reaction (one between matters of different phases), greater contact area between 2 matters, more frequent the collsision
temperatuer
greater the temp, higher the average kinetic energy pressed by the reactant molecules.
- energy required to overcome activational energy
catalyst
substance which accelerates a chemical reaction
pressure
more squished together, closer together
other complex compounds
CH4 = methane CH3CH2OH = ethanol NH3 = ammonia NH4 = ammonium
acid + metal =>
salt + hydrogen
eg. 2 HCl + Mg > MgCl2 = H2
acid + base (neutralisation) =>
salt + water
eg. HCl + NaOH > NaCl + H2O
acid + carbonate =>
salt + carbon dioxide + water
eg. H2SO4 + Na2CO3 > Na2SO4 + H2CO3
metal + oxygen =>
metal oxide
eg. 2 Fe + O2 > 2 FeO
acid + metal oxide =>
salt + water
HCl + NaOH > NaCl + H2O
precipitation reaction
occur when cations and anions in aqueous solution combine to form an insoluble ionic solid called a precipitate
(partner swap)
- help determine the presence of various ions in solution.
synthesis
combining 2 or more reactants into 1 (or more) products (s)
> more reactants from products
2 H2 + O2 = 2 H2O
A + B = AB
decomposition reaction
a single compound breaks apart into two or more elements or compounds (component elements).
- Usually energy is required to make this happen.
- less reactants, mroe products
SO2 = S + O2
AB = A + B
valency
8 - how many electrons in the outer shell
electron configuration
representation of the arrangement of electrons distributed among the orbital shells and subshells.
diatomic molecules
H2 ave N2 o F2 ear O2 f I2 ce Cl2 old B2 eer
have no fear of ice cold beer
balanced equations
in order to satisfy the law of conservation of matter, which states that in a closed system matter is neither created nor destroyed.
test for oxygen
glowing splint and place it in a sample of gas, if it re-ignites the gas is oxygen.
test of carbon dioxode
Light a splint, which is a long, thin strip of wood. Insert the lit splint into the tube with the gas. If carbon dioxide is in the tube, the flame will go out.
-When carbon dioxide is run through lime water, the water turns cloudy. This is because the water is a solution of calcium hydroxide, and when it reacts with carbon dioxide, a solid precipitate of calcium carbonate forms.
factors affecting corrosion
- More the reactivity of metal
- Presence of electrolytes (Oxygen) in water
- Presence of in natural water
- rise in temperature
- coated with layers of metals more active
- Humidity
factors affecting rusting
-Iron, Oxygen and Water (air moisture) combine
-can be accelerated when Iron is subjected to nature’s minerals, chemicals and temperature fluctuations.
-Any other form of acid
and corrosion stuff
energy levels
The electrons surrounding an atom are located in regions around the nucleus called “energy levels”.
represents the 3-dimensional space surrounding the nucleus where electrons are most likely to be.
-Each energy level is labeled with the quantum number n (n=1, 2, 3,…)
combining power of an element
the valency of the element
positive ions forms when
Metal atoms lose the electron, or electrons, in their highest energy level and become positively charged ions.
Anion
Non-metal atoms gain an electron, or electrons, from another atom to become negatively charged ions.
which one wants to lost and which wants to lose electrons
metal = wants to lost gas/nonmetal = wants to gain
base
slippery to touch and solvent in water
- potential for accepting rather than releasing hydrogen ions.
- accept a hydrogen ion (H+) from another substance
acids
form aqueous solutions with a sour taste and solvent in water
- defined as a compound (ion/molecule) that gives hydronium ions to another compound
