MCAT General Chemistry Practice Questions with Complete Solutions (100% Correct)

Alpha particle Correct Answer Helium-4 atom (2neutrons and 2protons) Beta + decay Correct Answer Conversion of proton to neutron and emission of positron (anti-electron) Beta - decay Correct Answer Coverts neutron to proton and a B- particle (electron) which is ejected Electron capture Correct Answer Capture of electron from closest valence shell and then used to concert proton into a neutron Gamma decay Correct Answer Expulsion of energy resulting from nucleus returning to ground state from excited state (usually after alpha or beta decay) Prefixes Correct Answer A nano a micro a milli a centi kilo mega Oxidation state rules Correct Answer Hydrogen has 1+ state when bonded to atom more electronegative than C, has 0 when bonded to C, and has 1- when bonded to atom less electronegative than C. Remember " fawn-cull-brisch." In peroxides ( H2O2 and Na2O2) oxygen is in a 1- oxidation state . Standard oxidation state? Correct Answer 0. Also the sum of oxidation states in a neutral atom must always add up to 0. "fawn-cull-brisch" Correct Answer F O N Cl Br I S C H... These are the electronegative atoms in descending order starting from most electronegative; bonds between H and anything before C will give H a 1+ oxidation state 1amu= Correct Answer Approximately 1 proton or 1 neutron. Hence 1 C atom is 12 amu Half-life Correct Answer Time it takes for one-half of a some sample of the substance to decay. Exponential decay equation Correct Answer N=N0(1/2)^t/(half-life time) or N=N0e^-kt Explain emission spectra Correct Answer Emission spectra is the emitted light from an atom after it passes through a prism and the bands of light correspond to specific wavelengths and energies corresponding to that atom