General Chemistry Final Exam Graded A+

General Chemistry Final Exam Graded A+ Convert Degrees Celsius to Kelvin T(K)= T(C) + 273.15 Absolute Zero for Celsius and Kelvin -273.15 C 0 K The unit size of the Celsius and Kelvin scale is the same. Boiling Point (C) and Kelvin and Freezing point Boiling: 100 deg. C and 373.15 K Freezing: 0 deg. C and 273.15 K Extensive properties Depends on the amount of the same Ex: mass and volume (these are physical properties) intensive properties independent of the amount of the sample -Only intensive properties can be used to identify the composition of the sample ex: density, color, temperature Density Calculation D=M/V D=g/mL nano- 10^-9 kilo- 10^3 centi- 10^-2 Micro 10^-6 milli 10^-3 mega 10^-6 millimeter to centimeter 1 m = .1 cm Atomic number for protons and how to calculate the number of protons Atomic number (Z) Number of protons is the atomic number Charge on an atom is determined by the number of protons in an atom. Therefore a neutral atom must have the same number of protons and electrons Isotopes atoms with the same number of protons but different number of neutrons ex: every chlorine atom has 17 protons, but the same chlorine nuclei have 18 neutrons and some have 20 neutrons. How to calculate isotopes protons, neutrons, and electrons: 133^Xe Protons: 54 (Atomic number) Electrons: 54 (protons = electrons) Neutrons: 54 + x = 133 (mass number is 133) x= 79 Avogadro's number 6.022 x 10^23 Elemental MM calculation The MM of any naturally occurring element is the weighted some of the contribution from its isotopes. Σ [(Fractional Abundance)(Isotopic MM)] (CO) Mon(o)- Carbon monoxide (SiO2) Di- Sulfur dioxide (NI3) Tri- Nitrogen triiodide (CBr4) Tetr(a)- Carbon tetrabromide (PCl5) Pent(a)- Phosphorus pentachloride (SF6) Hex(a)- Sulfur hexaflouride (IF7) Hept(a)- iodine heptafluoride B2H6 diborane CH4 methane NH3 ammonia H2O water HF hydrogen fluoride SiH4 silane PH3 phosphine H2S hydrogen sulfide HCl hydrogen chloride CaCO3 calcium carbonate Na2O sodium oxide Group IA elements are likely to have what charged ions? +1 Group IIA elements are likely to have what charged ions? +2 Group VIA elements are likely to have what charged ions? -2 Group VIIA elements are likely to have what charged ions? -1 Common polyatomic ions: ammonium NH4+ (Cation) Common polyatomic ions: hydronium H3O+ (cation) Common polyatomic ions: hydroxide OH- (diatomic anion) Common polyatomic ions: cyanide CN- (diatomic anion) Common polyatomic ions: carbonate CO3^2- (anion containing carbon) Common polyatomic ions: acetate CH3CO2^- (anion containing carbon) Common polyatomic ions: oxolate C2O4^2- (anion containing carbon) Common polyatomic ions: sulfite SO3^2- (Oxoanion) Common polyatomic ions: sulfate SO4^2- (oxoanion) Common polyatomic ions: nitrite NO2^- Common polyatomic ions: nitrate NO3^- Common polyatomic ions: phosphate PO4^3- Common polyatomic ions: permanganate MnO4^- Common polyatomic ions: chromate CrO4^-