Chem Help about lattice energy?
For the best answers, search on this site https://shorturl.im/avcKx Two factors that influence lattice energy (the amount of energy it takes to tear apart an ionic compound lattice into ions) include (1) the charge of the ions ... the larger the charge, the greater the attractive force between the ions (the force is proportional to the charge squared), and (2) the distance between the ionic nuclei ... the smaller the distance, the greater the attractive force. Based on charge, you would expect the compounds with +1 ions (KCl and RbBr) to have smaller lattice energies than the compounds with +2 ions (CaO and SrO). Between NaCl and RbBr, the Na+ and Cl- ions are much smaller than the Rb+ and Br- ions (making their nuclei closer), so the lattice energy of NaCl should be higher than RbBr. Between CaO and SrO, Sr2+ is larger than Ca2+, making the distance between the nuclei smallervfor CaO than for SrO. Thus, CaO has the larger lattice energy. CaO > SrO > NaCl > RbBr
Chemistry HELP: Lattice energies?
Given the following lattice energy of salt below in Kj/mol NaOH -900 Na2O -2481 CaO -3414 Mg(OH)2 -3006 MgO -3791 Al(OH)3 -5627 Al2O3 -15916 1. Why is the magnitude of lattice energy for NaOH smaller than that of Na2O? 2. Why is the magnitude of lattice energy for CaO smaller than that of MgO? 3. Why is the magnitude of lattice energy for NaOh smaller than that of Mg(OH)2?
Chemistry help: Lattice Energy?
Lattice Energy The following compounds all display the NaCl structure. (i.e. They are isomorphous.) For each pair, indicate which would have the lattice energy of lesser magnitude. CsF RbF SrO MgO SrSe SrS SrO NaI CaO CaSe
Help With Lattice Energy!?
Calculate the lattice energy of lithium fluoride, using the data in the table below. Show your work for full credit. Reaction: Description: Enthalpy: Li (s) → Li (g) :sublimation of lithium :+161 kJ/mol Li (g) → Li+ (g) + 1e :ionization of lithium :+520 kJ/mol F2 (g) → 2 F (g) :dissociation of fluorine molecule :+155 kJ/mol F (g) + 1 e → F (g) :electron affinity of fluorine atom :-328 kJ/mol Li (s) + 1/2 F2 (g) → LiF (s) : heat of formation of lithium fluoride :-617 kJ/mol Please I need help, i really tried and searched every where, but no one is clear. How do I do this, please explain and show me step by step please? Thanks ^_^
Help with lattice energies?
1. MgO, Rb2O, and Na2O From the Born–Landé equation [1] U ∝ (Z+×Z-)/(r+ + r-) where Z are the charges on the cation and anion, respectively; r+ and r- are radii of the cation and anion, respectively (Coulombic attraction term). The Z+×Z- term dominates. Only MgO has 2×2 (4) so it will have the highest U the others have Z+×Z- = 2. Of Rb2O and Na2O rNa^+< rRb^+ and hence Na2O has the smaller ro (r+ + r-) so it will have the next highest U hence in order of increasing U: U(Rb2O) (2163) < U(Na2O) (2481) < U(MgO) (3795) U calc values: CRC 12-26 kJ mol^-1 http://en.wikipedia.org/wiki/Born%E2%80%... 2. Lithium chloride, potassium bromide, and lithium sulfide Li2S (Z+×Z-) = 1×2 For LiCl and RbBr (Z+×Z-) = 1 so Li2S will have highest lattice energy (sulfides should not be used: covalent character). (rLi^+ + rCl^-) < (rK^+ + rBr^-) so U(LiCl) > U(KBr) U(KBr) (671) < U(LiCl) (834) < Li2S (2464)
Lattice energies?! help in chem please!?
There are two main ways to calculate the lattice energy, the Borne-Lande equation or the Kaputinskii equation. I personally prefer the Kaputinskii equation, as it is a little easier to calculate, I have used it on exams and homework. If you search for lattice energy in Wikipedia, it will give you the exact equation (subscripts usually don't copy from word documents very well).
CHEMISTRY HELP!!!!!!!!!!!!!?
The following is an actual question given on a University of Washington chemistry mid term examination paper. The answer was so "profound" that the professor shared it with colleagues, which is why we now have the pleasure of enjoying it as well. Bonus Question: Is Hell exothermic (gives off heat) or endothermic (absorbs heat)? Most of the students wrote proofs of their beliefs using Boyle's Law, which is that "gas cools off when it expands and heats up when it is compressed" or some variant. One student, however, wrote the following: First, we need to know how the mass of Hell is changing in time. So we need to know the rate that souls are moving into Hell and the rate they are leaving. I think that we can safely assume that once a soul gets to Hell, it will not leave. Therefore, no souls are leaving. As for how many souls are entering Hell, lets look at the different religions that exist in the world today. Some of these religions state that if you are not a member of their religion, you will go to Hell. Since there are more than one of these religions and since people do not belong to more than one religion, we can project that all souls go to Hell. With birth and death rates as they are, we can expect the number of souls in Hell to increase exponentially. Now, we look at the rate of change of the volume in Hell because Boyle's Law states that in order for the temperature and pressure in Hell to stay the same, the volume of Hell has to expand as souls are added. This gives two possibilities: If Hell is expanding at a slower rate than the rate at which souls enter Hell, then the temperature and pressure in Hell will increase until all Hell breaks loose. Of course, if Hell is expanding at a rate faster than the increase of souls in Hell, then the temperature and pressure will drop until Hell freezes over. So which is it? If we accept the postulate given to me by Ms. Teresa Banyan during my freshman year, "...that it will be a cold day in Hell before I sleep with you.", and take into account the fact that I still have not succeeded in having sexual relations with her, then option 2 cannot be true, and thus 1 am sure that Hell is exothermic and will not freeze. The student received the only A.
Chem help please! lattice energy?
Use the following information to calculate Delta Hlattice for MgF2. Mg(s) --> Mg(g) Delta H = 148 kJ F2(g) -> 2F(g) Delta H= 159 kJ Mg(g) -> Mg+(g)+e- Delta H = 738 kJ Mg+(g) -> Mg2+(g)+e- Delta H = 1450 kJ F(g)+e- -> F-(g) Delta H = -328 kJ Mg(s)+ F2(g) --> MgF2(s) Delta Hf = -1123 kJ
How to find the Lattice energy?!?
There is a good youtube video on lattice energy calculation given in the 1st link below. The 2nd and 3rd links below shows a diagram using the Born-Haber cycle. The 4th link is more of a text article that shows the Born-Haber cycle and uses Hess's law to calculate the lattice energy. Hope this information is helpful to you. JIL HIR
‘Na’ with atomic number 11 is called Sodium. The name is derived from the English word 'Soda' and discovered by Humphry Davy. Sodium is a soft metal that tarnishes within seconds of being exposed to the air. It also reacts vigorously with water.Sodium is used as a heat exchanger in some nuclear reactors, and as a reagent in the chemicals industry. But sodium salts have more uses than the metal itself.The most common compound of sodium is sodium chloride (common salt). It is added to food and used to de-ice roads in winter. It is also used as a feedstock for the chemical industry.Sodium carbonate (washing soda) is also a useful sodium salt. It is used as a water softener.Sodium is the sixth most common element on Earth, and makes up 2.6% of the Earth’s crust. The most common compound is sodium chloride. This very soluble salt has been leached into the oceans over the lifetime of the planet, but many salt beds or ‘lakes’ are found where ancient seas have evaporated. It is also found in many minerals including cryolite, zeolite and sodalite.Because sodium is so reactive it is never found as the metal in nature. Sodium metal is produced by electrolysis of dry molten sodium chloride.Hope it helps you. Thanks for A2A. :)-Dixit Shubhashish