A sample of Se weighs 20.5 grams. Will a sample of V that contains the same number of atoms weigh more or less than 20.5 grams? (more, less): _______
Calculate the mass of a sample of V that contains the same number of atoms. _______ grams of V
Answer:
Since the atomic weight of V is smaller than the atomic weight of Se, each atom will have a smallermass, and the sample will weigh less.
Since the same number of moles will contain the same number of atoms, regardless of the element, it is only necessary to find the number of moles of Se in the 20.5 gram sample, and then to find the mass of the same number of moles of V.
The atomic weight of Se is 79.0 g/mol
1. Convert grams of Se to moles of Se:
moles Se= 20.5 g Se1 mol = 0.260 mol Se79.0 g
Multiply by moles per gram. Grams cancel out.
The atomic weight of V is 50.9 g/mol
2. To convert 0.260 moles of V to grams of V:
grams V = 0.260 mol V50.9 g = 13.2 g V1 mol
Multiply by grams per mole. Moles cancel out.
A gram atomic mass of helium (He) contains the same number of atoms as 1 mole of helium. Since 1 mole of any substance contains approximately 6.022 x 10^23 atoms, a sample of helium with a gram atomic mass would contain that same number of atoms.
The number of atoms is 1,50553521.10e23.
The total number of atoms contained in a 1,00 mole sample of helium is 6,022 140 857.10e23.
Take the actual sample weight of 13grams, and divide it by the atomic weight of chromium. This gives you your molar percentage of atoms. Now multiply this molar percentage by Avogadro's constant, the number of atoms in one mole, and this will give you your number of atoms in the sample.
If a sample of an element contains atoms of different mass numbers, the name of the element followed by a hyphen and the mass number is the name of an isotope of the element.
Which sample contains the greatest number of atoms. A sample of Mn that contains 3.29E+24 atoms or a 5.18 mole sample of I?The sample of _____ contains the greatest number of atoms.Answer:In order to compare the two samples, it is necessary to express both quantities in the same units. Since the question was phrased in terms of atoms, it is convenient to convert moles of I to atoms of I.The conversion factor between atoms and moles is Avogadro's number: 6.02 x 1023 "things" / molTo convert 5.18 moles of I to atoms of I:atoms I= 5.18 mol I6.02 x 1023 atoms I = 3.12E+24 atoms I1 mol IMultiply by atoms per mole. Moles cancel out.The sample of Mn contains 3.29E+24 atoms.Since 3.12E+24 is smaller than 3.29E+24, the sample of Mn contains the greatest number of atoms.
Which sample contains the greatest number of atoms. A sample of Al that contains 8.18E+23 atoms or a 5.16 mole sample of S?The sample of______ contains the greatest number of atoms.Answer:In order to compare the two samples, it is necessary to express both quantities in the same units. Since the question was phrased in terms of atoms, it is convenient to convert moles of S to atoms of S.The conversion factor between atoms and moles is Avogadro's number: 6.02 x 1023 "things" / molTo convert 5.16 moles of S to atoms of S:atoms S=5.16 mol S6.02 x 1023 atoms S= 3.11E+24 atoms S1 mol SMultiply by atoms per mole. Moles cancel out.The sample of Al contains 8.18E+23 atoms.Since 3.11E+24 is larger than 8.18E+23, the sample of S contains the greatest number of atoms.
A gram atomic mass of helium (He) contains the same number of atoms as 1 mole of helium. Since 1 mole of any substance contains approximately 6.022 x 10^23 atoms, a sample of helium with a gram atomic mass would contain that same number of atoms.
Whatever be the substance the one gram mole of that substance would have 6.023 x 1023 atoms or molecules or ions in it. Hence to get the mole just divide the number given by 6.023 x 1023
The gram atomic mass of phosphorus is 30.9738, and by definition, a mole of such atoms contains Avogadro's Number of atoms. Therefore, 100 g of phosphorus contains 100/30.9738 or 3.23 moles, to the justified number of significant digits.
one mole of all substances contains 6.022 x 10^23 atoms =number of atoms in 22400 cm^3 of any gas at STP
This depends on the mass of the gold sample.
The number of atoms is 1,50553521.10e23.
The total number of atoms contained in a 1,00 mole sample of helium is 6,022 140 857.10e23.
150 (50 x 3)
The gram Atomic Mass of lithium is 6.941; this is the amount of lithium that contains Avogadro's Number of atoms. Therefore, in 18.7 g of lithium, there will be (18.7)/(6.941) times Avogadro's Number of atoms, or about 1.62 X 1024, to the justified number of significant digits.
Take the actual sample weight of 13grams, and divide it by the atomic weight of chromium. This gives you your molar percentage of atoms. Now multiply this molar percentage by Avogadro's constant, the number of atoms in one mole, and this will give you your number of atoms in the sample.