what is 1st ionization energy?
443622
For element X the amount of energy required to remove one of the the outermost electrons to make the ion X+ (hence the name Ionisation)
309162
The first energy level is the atoms ground state, electrons will not release any phtons from this level since they are stable at this point.\n\nJust because an electron is in thr 7th level does not mean that it will release 7 photons to return to its ground state.  The electron could release 7 photons and jump 1 level each time, that is possible, but not required.  It is also possible that the electron release just 1 photon carrying a lot of energy and jump down all 7 levels at once.  The number of energy levels the electron jumps down depends on the energy it releases in the photon, or vice-versa, the energy it releases in a photon determines how many levels it jumps down.
745401
There are two rules to use:\n1) The lattice energy between ions of opposite charge is strongest when the ions are small.\n2) The lattice energies  increase rapidly as the charge on the ion becomes larger.\n\nThe first rule implies that  LE(PbF2) > LE(PbCl2), in absolute value.\nThe second implies that   LE(PbF4) > LE(PbF2) and  LE(Pb2O3) > LE (PbF4)\nTherefore we have  LE(Pb2O3) > LE (PbF4) > LE(PbF2) > LE(PbCl2)  still in absolute value.\n\nConclusion:  3c 2d 1a 2b
485922
the minimum amount of energy required to start a reaction
1122951
1 electron, 0 neutrons
843857
Should be D...\n\nPeriodic trend of Ionization energy is the same as electronegativity. Increases going Top Right. Compared to Lithium we can't tell which one takes preference, but since we're considering Mg+, it already had it's first electron removed. In this problem we are looking at second ionization energy. Second electron is always much harder to remove than the first one, so second IE (ionization energy) is always much greater than first IE.  A is false.\n\nElectron affinity is the energy required to add an electron to an atom. Ionization is the energy required to take away an electron from an atom. So they are equal and opposite in sign, but we have to look at the equations of electron addition and removal.\n\nMg+-->Mg(2+) + e- (Removal, Ionization Energy)\nMg(2+) + e- -->Mg+ (Addition, Electron Affinity)\n\nThe equations are just reversed, so by Hess's Law Ionization energy of Mg+ is equal to and opposite in sign from Electron affinity of Mg(2+)
258486
This is a more complicated question than it appears.  You didn't include to what degree you were seeking this information, so rather than go into a great deal of explanation I have included a link that explains and tabulates the basics of electron energy levels.  Hope this helps.
748503
s p d f blocks tell which set of orbitals are the last to fill for those elements.\n\n+ or - depending on whether it will lose or gain an e-\n\ncations are smaller than atoms b/c they lose e-\nanions are larger than atoms b/c they gain e-\n\neach successive ionization energy gets higher becasue the #protons is more and more unbalanced by # e-\n\nhalogens have 7 valence e- and noble gases have 8.  by gaining one e- the halogens now have the e- configuration of a noble gas and are more stable.  gain 1 e- = 1- charge
389811
In the world of quantum mechanics, the "ground state" is the first orbital where an electron can be found.  Any orbital above the first has an electron in an "excited state", since it must gain one or more quanta of energy to get to a higher level.
316710
well energy is used only in the beginning to start the reaction. otherwise an exothermic reaction will give out tremendous amount of heat energy.
895120
The correct answer is 3.\nThe 1st spectral line is caused by the electron falling from state 2 to state1.  The 2nd line is caused by a shift from 3 to 2, and the third, a shift from 3 to 1.
801581
the answer is d.\nIonization evergy - the energy required to remove the lease tightly bonded elctron from a ground-state atom in the gaseous state.
873114
→ Atomic radius decreases → Ionization energy increases → Electronegativity increases →\n\nIn general, the degree of electronegativity decreases down each group and increases across the periods, as shown below. Across a period, non-metals tend to gain electrons and metals tend to lose them due to the atom striving to achieve a stable octet. Down a group, the nuclear charge has less effect on the outermost shells. Therefore, the most electronegative atoms can be found in the upper, right hand side of the periodic table, and the least electronegative elements can be found at the bottom left. \n\nGenerally speaking, atomic ionization energies decrease down a group of the periodic table, and increase left-to-right across a period. Ionization energy exhibits a strong negative correlation with atomic radius.
1067423
The change of energy  between energy levels.\n\nEnergy of electron in it's higher state  - energy of electron in it's lower state = h*f\n\nI forgot how to calculate the electron's energy at a specific energy state, but it should be easy to find.
761199
Although there is a general trend toward an increase in the first ionization energy as we go from left to right across this row, there are two minor inversions in this pattern. The first ionization energy of boron is smaller than beryllium, and the first ionization energy of oxygen is smaller than nitrogen.\n\nTo read about why, follow the link. It's really hard to explain
139259
I'm not sure what you are asking.  Here are two possible answers:\n\nFirst:  E = h*nu\n\nIs the equation for the amount of quantized energy in light where h is Planck's constant, 6.626e-34 Joule seconds, and nu is the frequency in Hertz.\n\nThis determines the "raw" energy in the light.  As you know, going from electricity back to light varies in efficiency.  An electric light bulb requires much more electricity than a flourescent bulb to produce the same amount of light.\n\nSecond: hf = phi + Ek\n\nThis is the equation for the photoelectric effect, where electrons are ejected from a material being struck by light.  h is again Planck's constant and f is the frequency of the incident photon.  Phi is the amount of energy required to remove an electron from its binding and Ek is the kinetic energy observed.
874452
They are just one electron away from achieving an octet.  So they require lower energy to lose this electron in a reaction.