a quantity of sodium (22.99 atomic mass) contains 6.02(10^23) atoms, the mass of sodium is...?
961946
one mole of a substance is 6.02x10^23 (avogadro's number) atoms. so... you have one mole.\nso from this, there would be 22.99 grams.\n\nexplained:\nn(moles) = m(mass) / M(molecular wt.)\n1 = m / 22.99\nm = 1 * 22.99\nm = 22.99 g \n\n:-)
479787
In 100g of solution that is 5% by mass NaCl, there are 95 g H2O and 5g Nacl.\nYou want 250g of solution...set up a simple ratio:\n95g H2O/100g Soln = ?g H2O/250g Soln\n? = 237.5g H2O
986602
K-weighs 39.03 x 2 atoms=78.06\nS= weighs 32.06\nO-15.99 x 4 atoms=63.96\nadd them all up\n174.08 is your answer
1141237
depends if it is 25.9% nitrogen by molar weight or total # of atoms
34174
(X atoms)/(6.02x10^23 atoms/mol) = Y moles\n\n(Y moles)*(6.02x10^23 atoms/mol) = X atoms
666341
A mole is a unit used to calculate the amount of atoms. One mole has 6.02*10^23 atoms in it.\n\nThe Ar is the Molar Mass of an Atom, a lab-determined weight used to calculate the number of moles.\n\nn = m/Ar, where n = Number of Moles, m = mass and Mr = Molar Mass of Atom.\n\nThe Mr is the Molar Mass of the Molecule, basically all the Ars added together. i.e. NaCl has an Ar of (23 [Na] + 35.45 [Cl]) = 58.45.\n\nUsually the mole formula is written as n = m/Mr as most problems will involve more than one atom ratio.
819588
number of atoms (of each element) on one side equals the other side.
798854
Cause Na, Sodium has 11 electrons, its electron configuration would be 1s2 2s2 2p6 3s1
148855
Note that mass number is not the same thing as atomic mass; mass number is always a whole number, whereas atomic mass is always an average of the various isotopes of that element.  Lithium can have a mass number of 6, but it's more commonly 7, and its atomic mass is 6.941.
1033737
A grain of salt weighs about 0.00010 g.\nThe atomic mass of NaCl is about 58.5 g/mol.\nAvogadro's number is 6.022x10^23 molecules/mol.\n\n0.00010 (g/grain) / 58.5 (g/mol) x 6.022x10^23 (molecules/mol)\n=\n1.03 x10^18 molecules/grain
145956
MY ANSWER IS :\n\n18.2g  of Na2S is produced.
215367
1 mole occupies-----22.4lts\n??????   -----------5.6lts\n\n5.6/22.4=0.25
134686
An atom of neon has an atomic mass of 20
145088
its nice, because the molecular weight of a compound in grams = 1 mol of that compound. It makes it easy this way to figure out equations involving mol gram ratios. \n\nAlso, remember 6.022 x 10 to the 23rd power. \n\n1 mol X atoms - 6.022 x 10^23 X atoms\n6.022 x 10^23 X atoms = blank grams X\n1 mol X atoms - blank grams X
1138448
Look on a periodic table.\n\nIt should be listed below the atomic number as a decimal value.  The mass number is an average mass (in atomic mass units) of an element, based on different isotopes.  It equals the number of protons + the number of neutrons in the nucleus.
930413
6.37 moles of any molecular substance just contains 6.37 times Avogadro's number of molecules, because a mole of matter always contains a mole of particles, that is, Avogadro's number many.  6.37*6.022 x 10^23 = 3.84 x 10^24.
750574
3.01E23 atoms of tin is about one-half mole (one mole is Avogadro's number -- 6.023E23 -- of anything).  So, which of the numbers you give is roughly one-half of the atomic weight of tin -- 118.69 grams/mole?