how do you find the percent of mass?
342540
Take the mass of the substance of interest, divide it by the total mass, mulitply by 100.\n\nIf you need to find the percent of an element within a compound, you convert mass of the compound to moles, and then determine the number of moles. \n\nThe number of moles of the compound will be equal to the number of moles of the element multiplied by however many atoms of that element are in the compound.\n\nFor example, if you have 3 moles of NH4OH, then you have 3 moles of N in that compound, and 15 moles of H in the same compound.\n\nOnce you have the number of moles of your element of interest, you convert it back to grams. Then divide that by the total weight of the compound and multiply by 100.\n\nHope I haven't been too confusing.
546865
First, it seems to have only 2 isotopes.  \n\nYou need to take each mass and multiply by its percentage.  Then add the two resulting numbers together.  You then have the weighted average mass for the element, or average atomic mass.  This weighted average atomic mass is the one reported on the periodic table of elements.\n\n35 x 40%\n+\n37 x 60%
1138340
First, you need to multiply this number with the volume you are given in mL to obtain the mass because you are given a density measure (mass per volume). Then, divide by 10^6 because ug means microgram, or a millionth of a gram.
1121653
density=mass/volume or something like that, so if u have the density and the volume (aproximations ofcourse) u can find the mass\n\ni think! lol
92631
To calculate percentage:\n\nDivide the part by the whole.  10 cats out of  100 cats is equal to 10 divided by 100 or .10. You then you multiple by 100 to get the percentage.   .10 times 100 equals 10 percent.\n\nIf you know the percentage:\n\nDivide by 100 and then multiple the whole by the resulting number to get the portion. 10 percent of 100 cats equals 10 divided by 100 times 100. 10 divided by 100 equals .10 now .10 times 100 equals 10 or 10 cats out of 100 cats.
167644
Divide it using decimals then multply the decimal by 100 and that will be your percent\n\nIs it just me or did someone else use this same exact answer below.  seriously people use your own imaginations and brains.
280201
Density = mass/volume
578713
U can a measure the mass of an object accurately using a Physical Balance.\nUnit of mass is kg in SI unit ysstem.\nMore accurate ways of measuring mass is done now.\n\nU can calculate it's weight by a formulae:\nW=mg.\nW-Wieght\nm-mass\ng-aceleration due to gravity (9.8 ms^-2)
24900
33 percent by mass. The sugar forms 25/(25+50) of the total mass, or 1/3. This is roughly 33%.
95798
I'm thinking concentration, but your question is worded sort of oddly... Does that fit with what you've been learning????  It's usually percent by mass I think...
1158383
the most common formulas involving mass and density are:\n\nD=M/V     (D is density, M is mass, and V is volume.   \n                the "/" sign means division)\n\nyou can use this equation to find other equations.\n\nVD=M        (Volume times Density equals Mass)\n\nM/D=V        (Mass divided by Density equals Volume)\n\n\nas far as definitions for mass and density, mass is how much matter is contained in an object and density is the ratio of the amount of matter to the amount of space it takes up.
738420
To calculate atomic mass of an element, it is just a weighted average of the naturally occuring isotopes.  For example:\n\nIf element A has two isotopes, A-23 and A-24, the masses are 23.5 and 24.5 respectively, and the percentage abundance is 93.0% for A-23 and 7.00% for A-24, you would:\n\nMultiply mass of A-23 (23.5g) to the decimal of the percentage (ie.  93.0%/100 = .930).  You would then do the same thing with A-24, and now you will have two numbers.  The final step, you sum the two numbers you obtained by the previous calculations.\n\nI know this is a general example with a made up element and made up numbers, but it is all that comes to mind when I read your question.  I hope this helps.
349502
Find the weight the object (with a precision scales) and its volume (put it in water and look at the amount displaced).\n\nCalculate the density = weight (in gram) / volume (in milliliter)\n\nYou will find a number lying between 19.3 (density of pure gold) and 8.92 (density of pure copper). Say you found 18 gram/ml\n\nThen the amount of gold is   (18-8.92)/(19.3-8,92) = 87.5% gold
732664
First convert it to a decimal by dividing the denominator into the numerator:\n27/40=0.675\n\nThen move the decimal point two places to the right (multiply by one hundred) to convert it to percent form:\n67.5%
824559
Mass is measured in grams.
979025
1. calculate the no. of mol of resulting MgO\n2. from the first eqn, 3 moles of MgO results from 1 mol of Mg3N2, find the no. of mol of Mg3N2\n3. then calculate grams of Mg3N2 (since all Mg3N2 must react with water)\n4. and find the percentage by grams (Mg3N2/0.470 g) x 100%
717832
http://dbhs.wvusd.k12.ca.us/webdocs/Mole/Grams-to-Moles.html\n\nAbout sums it up.  Find grams (usually given), then divide by molecular mass (grams per mole).