2.0E-9 Newton of force is needed to break a Si - C bond. \nAssume the bond must be stretched by a distance of 200. picometre before it is broken.Estimate the bond energy in KiloJoule/mol.
208982
E = Fd = (2E-9 N) (200E-12 m) = x J\nx J (1 kJ / 1000 J) = xE-3 kJ\n\nI think this is already per mol...
349803
Bond enthalpy at 25 C\nC-H = 99 kcal/mole\nC-C = 83 kcal/mole\nC=C = 147 kcal/mole.\n\n(1st C) = 3 * 99 + 83 = 380 kcal/mole\n(2nd C) = 99 + 83 +147 = 329 kcal/mole\n(3rd C) = 2 * 99 + 147 = 345 kcal/mole
471582
a) 4\n\nEach covalent bond has 2 electrons.
230398
http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/posfe.html#c3\n\nThe link above may be of some help. Input the values you want or need.
555081
Energy = force * distance\n= 100 N * 6 m = 600 J\n\nAnswer is d
95575
im highly sceptical on that, because the bond angle of carbon is different from other chemicals, but if one was to be formed, i would imagine silicone or germanium would form it, although, silicone forms stronger bonds, which cant bend that easily, I THINK... not perticularly true... just an assumption on my part
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www.visionlearning.com/library/module_viewer.php?mid=55 - 66k \n\nwww.biology.arizona.edu/biochemistry/ tutorials/chemistry/page2.html - 7k - \n\nhttp://en.wikipedia.org/wiki/Chemical_bond
187032
http://toolsformoney.com/bond_calculator.htm
396344
Sanity check. Ultraviolet light is energetic light, which will break bonds, which is why it can be dangerous. UV light is shorter than about 400 nm. So after throwing around the big exponents, we want an answer less than 400 nm, but probably larger than 100 because then it's x-rays, which is usually overkill for breaking molecules apart. \n941 kJ / mol means 941,000 joules are sufficient to break \n6.02x10^23 molecular bonds. ( 1 mol is Avagadro's number)\ndivide it out and get how much to break just one N2 bond:\n941,000 J / 6.02x10^23 molecules = 1.56 x 10^-18 joules\nWhat wavelength of light corresponds to that amount of energy being packed into one photon? \nE = hc / lambda, where h = 6.63x10^-34 m2 kg/s (Planck), c = 2.228x10^8 m/s (speed of light), and lambda is wavelength in meters (staying in mks units, E will be in joules). Solve for lambda, where E is 1.56 x 10^-18. \nlambda = hc/E = 1.274 x 10^-7 meters\nmultiply by 10^9 to get nm, then lambda = 127.4 nm\nLooks good to me...  There might be a simpler cookbook equation to get this answer, but it's good to know how to do it from the basic constants of nature. \n\nNote: previous answer left out factor of Avagadro's number and did no sanity check...
484381
Calculate the k value for the spring.  The stone exerts a force of 8*9.8 = 78.4 N and a compression of 9 cm is\n78.4/.09 = 871 N/m. (Keep it in the MKS system ☺)\n\nWhen the spring is pushed down another 30 cm its total deflection is 39 cm and it's total potential energy is \nkx²/2 = 871(.39)²/2 = 132.5 J\n\nThe stone acquires 132.5 J of gravitational potential energy when released.\n\nSince gravitational potential is mgh, then\n8*9.8*h = 132.5 or h = 1.69meters\n\n\nDoug
510887
Mass is 3500 kg.  Distance moved is 200 meters (up).\n\nForce is usually calculated as mass times acceleration.  The SI unit used to measure force is the newton (symbol N), which is equivalent to kg*m/s^2.  The acceleration here is the acceleration due to gravity or\n\ng = 9.80665 m/s2\n\nThe force = m*g = 3500 kg * 9.81 m/s^2 = 34335 Newtons.\n\nThe energy (or work done) is the force times the height or\n\n34335 Newtons * 200 meters = 686700 joules.\n\nTo calculate the power required, you would have to know how long the movement took in seconds.
5714
Interesting scenario first of all i would like to comment. Well actually the bond is due to electronic forces. Hence mass has litle effect on the bond strength. Thus i thikn the effect of mass change should be a small one!! unless you change the charge of proton too!!
396265
try the formulas:\n\nforce = mass * aceleration\n\nwork = force * distance\n\n\n\n\nWell i dont speak english very well, but i hope i help u.\n\nKisses
602501
I think knowledge of the terms electronegativity and bond energy address your question. \n\nElectronegativity refers to the difference by which two atoms tend to hold onto electrons. You should be able to find a periodic table that shows you the electronegative values of all the atoms. You can compute the electronegativity of a bond between two atoms by subtracting their values from each other (based on Linus Pauling's calculations). For example, Flourine (F) has an electronegativity value of 4 and Na = .9. The electronegative value of an F-Na bond is 3.1 (4 - .9). My old high school textbook (Heath) states that ionic bonds are those having an electronegative difference between 1.7 and 4; polar covalent bonds are between 0.2 and 1.7; covalent (non-polar) bonds are between 0 and 0.2. Thus an F-Na bond by this classification system is an ionic bond.\n\nBut I suppose to answer your question most directly, I would say the evidence that ionic bonds are strong concern something called bond energy. That is, the difference between how much energy is needed to make and break chemical bonds. Generally speaking, the higher the electronegative difference (which translates into more of an ionic bond--see calculation above), the more energy required to break such bonds. \n\nThe bottom line, is that I think this translates into something like the observed boiling points of various substances. Substances that have strong ionic bonds (again, determined by calculation above) I believe have a higher boiling point (because it takes more energy/heat) to break the bonds.
493320
In all cases the arragngement is tetrahedral and thus the ideal bond angle would be 109.5 degrees. In detail:\n\na) O has 2 unpaired e and 2 lone pairs. In H3O+, the 2 e participate in two single bonds with H and one lone pair participates in a dative bond with H+. Thus you have 3 single bonds + 1 lone pair so the arrangement is tetrahedral. lone pair-bond electron repulsion is stronger than bond electron-bond electron and thus the actual bond angles will be smaller.\nThe shape of the molecule will be trigonal pyramid (It is actually tetrahedral with O in the center and on one corner you have the lone pair but the lone pair is not "visible" in the molecular level)\n\nb) Si belongs to the same group as C. It forms 4 identical single  bonds in SiCl4 and has no lone pairs. Thus both the molecular shape and the electron arrangement are normal tetrahedral with bond angles 109.5\n\nc)N has 3 unpaired e and one lone pair. In NF3 it forms 3 single bonds through the unpaired e and so it has 3 bonds + 1 lone pair. Thus it is similar to H3O+ (tetrahedral electron arrangement, ideal bond angle 109.5, true bond angle smaller, molecular shape trigonal pyramid)
190208
OK... \n\nin CH4 there are 4 C-H bonds that take 1646 kJ... divide by 4 to get energy per C-H bond (call it x)\n\nin C3H8, there are 2 C-C bonds (draw structure) and 8 C-H bonds. so from 4006, subtract 8x (for 8 C-H bonds) so you get answer for 2 C-C bonds. Then divide by 2 to get bond energy of one C-C bond.
131976
Because the bonds between the atoms are very strong, it takes a lot of energy to break them.