Answering "http://wiki.answers.com/Q/How_do_you_calculated_the_percentage_of_an_isomer_using_proton_nmr"
ppm is parts per million and thus a concentration. It can not be calculated from molecular weight.
When alkynyl molecules are placed in NMR instrument the induced magnetic field of molecules are in Diamagnetic region of external magnetic field. There fore the resultant energy will be low
NMR print outs are usually rounded to three decimal places, A rounding 'error' of 0.001 will equate to a J value 'error' of 0.3 (on a 300 MHz machine.)
5 mg of an element or compound in 1 L of solution
about 1.6 ppm, but you don't always see it
Here is how you calculate a coupling constant J: For the simple case of a doublet, the coupling constant is the difference between two peaks. The trick is that J is measured in Hz, not ppm. The first thing to do is convert the peaks from ppm into Hz. Suppose we have one peak at 4.260 ppm and another at 4.247 ppm. To get Hz, just multiply these values by the field strength in mHz. If we used a 500 mHz NMR machine, our peaks are at 2130 Hz and 2123.5 respectively. The J value is just the difference. In this case it is 2130 - 2123.5 = 6.5 Hz This can get more difficult if a proton is split by more than one other proton, especially if the protons are not identical.
Here is how you calculate a coupling constant J: For the simple case of a doublet, the coupling constant is the difference between two peaks. The trick is that J is measured in Hz, not ppm. The first thing to do is convert the peaks from ppm into Hz. Suppose we have one peak at 4.260 ppm and another at 4.247 ppm. To get Hz, just multiply these values by the field strength in mHz. If we used a 500 mHz NMR machine, our peaks are at 2130 Hz and 2123.5 respectively. The J value is just the difference. In this case it is 2130 - 2123.5 = 6.5 Hz This can get more difficult if a proton is split by more than one other proton, especially if the protons are not identical.
for a triplet. You have to take the (difference between the middle and one of the outer frequencies)* the frequency in MHZ
In chemistry, parts per million or ppm is defined as the number of part of a solute that is in one million parts of a solution. The formula to calculate ppm is to divide the mass of the solute in grams by the combined mass of the solvent and solute also in grams. This value is multiplied by 1,000,000 ppm.
Here is how you calculate a coupling constant J: For the simple case of a doublet, the coupling constant is the difference between two peaks. The trick is that J is measure in Hz, not ppm. The first thing to do is convert the peaks from ppm into Hz. Suppose we have one peak at 4.260 ppm and another at 4.247 ppm. To get Hz, just multiply these values by the field strength in mHz. If we used a 500 mHz NMR machine, our peaks are at 2130 Hz and 2123.5 respectively. The J value is just the difference. In this case it is 2130 - 2123.5 = 6.5 Hz This can get more difficult if a proton is split by more than one other proton, especially if the protons are not identical.
Here is how you calculate a coupling constant J: For the simple case of a doublet, the coupling constant is the difference between two peaks. The trick is that J is measured in Hz, not ppm. The first thing to do is convert the peaks from ppm into Hz. Suppose we have one peak at 4.260 ppm and another at 4.247 ppm. To get Hz, just multiply these values by the field strength in mHz. If we used a 500 mHz NMR machine, our peaks are at 2130 Hz and 2123.5 respectively. The J value is just the difference. In this case it is 2130 - 2123.5 = 6.5 Hz This can get more difficult if a proton is split by more than one other proton, especially if the protons are not identical.
Deuterium has a nuclear spin of 1; causes the C-13 signal to be split into a triplet at 77.0 ppm
Answering "http://wiki.answers.com/Q/How_do_you_calculated_the_percentage_of_an_isomer_using_proton_nmr"
ppm is parts per million and thus a concentration. It can not be calculated from molecular weight.
When alkynyl molecules are placed in NMR instrument the induced magnetic field of molecules are in Diamagnetic region of external magnetic field. There fore the resultant energy will be low
NMR Spectroscopy Use molecule Structure FT NMR Use Different No. of mass Structure