A 25.12 g sample contains 1.00 mol of atoms, 25% of them Ar and 75% of them element X. What is element X?

Q: Explain clearly what is meant by the statement “The atomic mass of gold is 197.0 amu.”

A: “The atomic mass of gold is 197.0 amu.” The explanation of the above statement has to be given…

Q: If 4.18x10^22 atoms of element Y have a mass of 2.46g what is the identity of element Y

A:

Q: The density of helium in a balloon is 1.18 g/L. If a balloon holds 2.89 L of He, how many atoms of…

A: Since mass of He = density X volume  density of He = 1.18 g/L Volume of balloon = 2.89 L => mass…

Q: How many silicon atoms are there in 1.00g of silicon?

A: Given: Mass of silicon=1.00 g Mass of 1 mole of silicon=28.0855  g

Q: How many miles of gold atoms do 3.45 x 10^24 gold atoms constitute

A: This problem can be solved by knowing that one mole comprises of 6.022×1023 atoms.…

Q: Calculate the mass (in grams) of 1.50 mol of Na.

A: Given  moles of Na = 1.50 mol molar mass of Na = 23 g/mol Formula used -  mass = moles x molar mass…

Q: What is the mass of 2 moles of NH3? (Hint: 1 molecule of NH3 has a mass of 17 amu) * O 17 amu O 17 g…

A:

Q: How many moles of Na are there in 1.28 x1025 atoms of Na?

A:

Q: An unknown element X has the following isotopes: ¹⁰X (20.00% abundant) and ¹¹X (80.00% abundant).…

A: The term isotopes can be defined as the variants of a given chemical element that differ in neutron…

Q: Calculate the mass, in grams, of 262 atoms of cesium, Cs (1 mol of Cs has a mass of 132.91 g).

A: Molar mass = 132.91g I mol of Cs contains 6.022×1023atoms  Therefore mass of 6.022 × 1023 atoms =…

Q: A compound of iodine and cesium contains 63.94 g of metal and 61.06 g of nonmetal. How many grams of…

A:

Q: The density of helium in a balloon is 1.18 g/L. If a balloon holds 2.91 L of He, how many atoms of…

A: Calculation of mass of Helium: Mass=Volume×density=2.91 L×1.18 g/L=3.4338 g Calculation of no. of…

Q: The density of helium in a balloon is 1.18 g/L. If a balloon holds 2.95 L of He, how many atoms of…

A: It is given that :Density of helium in a balloon = 1.18 g/LVolume = 2.95 L

Q: 4. What is the mass of 7.75 moles of magnesium metal?

A:

Q: An unknown element X has the following isotopes: 140X (89.00% abundant) and 142X(11.00% abundant).…

A: Since,         Average Atomic mass=Σass of Isotope×% of Isotope100

Q: The density of helium in a balloon is 1.18 g/L. If a balloon holds 2.93 L of He, how many atoms of…

A: The mass of the species can be defined as the product of the density of the species and the volume…

Q: A sample of aluminum foil contains 4.50×1023 atoms.4.50×1023 atoms. What is the mass of the foil?

A: Given,  Number of atoms of Al foil = 4.50 x 1023 atoms  Mass of the Al foil = ?

Q: How many silver atoms are contained in 1.75 moles of silver?

A: 1 mole of a substance is equal to the Avogadro number of atoms.  1 mole =6.022 x 1023 atoms.

Q: When barium (Ba) reacts with sulfur (S) to form barium sulfide (BaS), each Ba atom reacts with an S…

A: Calculate the amount of S. Mass of the sulfur=Volume (density) Mass of the sulfur=1.75 cm3(2.07…

Q: The density of helium in a balloon is 1.18 g/L. If a balloon holds 2.99 L of He, how many atoms of…

A:

Q: Tin has 10 stableisotopes. The heaviest, 124Sn, makes up 5.80% of naturally occurring tin atoms. How…

A: Given that,  124Sn isotope makes up 5.80% of naturally occuring tin atoms  Mass of tin sample = 57.0…

Q: How many Sn atoms are there in a 96.2 gram sample of Sn ? atoms

A:

Q: An unknown element X has the following isotopes: ¹⁴⁰X (89.00% abundant) and ¹⁴²X(11.00% abundant).…

A:

Q: What is the mass of 1.6x10^21 argon atoms?

A: Molar mass of Argon is 39.95 g/mol i.e 1 mole of argon = 39.95 g of Argon Number of atoms of Argon…

Q: What is the mass in grams of 6.022 * 1023 N atoms of mass 14.01 amu?

A: To determine the mass in grams of 6.022x1023 N atoms of mass 14.01 amu Given that: Mass of each atom…

Q: How many moles of silver are 1.8x10^20 atoms of silver ?

A:

Q: A sample of aluminum foil contains 6.50×1023 atoms.6.50×1023 atoms. What is the mass of the foil?

A: Mole concept: The number of molecules or atoms present in the one mole of the substance is equal to…

Q: How many atoms of tritium are in 1 kg of tritium water ³H₂O?

A: Number of mol = Mass/molar mass Number of atoms in 1 mol = 6.0224 x 1023

Q: What mass (in g) does 3.99 moles of Kr have?

A: Given:Number of moles of Kr = 3.99 molesMolecular mass of Kr is known(from the periodic table) =…

Q: What is the mass of a sample containing 1.00 mol of atoms, 33% of them N and 67% of them O?

A: The objective of the question is to calculate the mass of a sample containing 1.00 mol of atoms, 33%…

Q: An atom consists of two isotopes, the first with an atomic mass of 15.8967 amu and the second with…

A: Atomic mass of first Isotope = 15.8967 amu Atomic mass of second Isotope = 16.8245 amu Average mass…

Q: An unknown element X has the following isotopes: ²⁵X (80.5% abundant) and ²⁷X (19.5% abundant). What…

A: Given :  element X has the isotopes: ²⁵X (80.5% abundant) and ²⁷X (19.5% abundant).  Since Atomic…

Q: How many ATOMS of sulfur are present in 3.39 grams of sulfur tetrafluoride ?

A:

Q: 5.061 g of a hydrated metal sulfate is heated only 2.472 g of anhydrous metal sulfate remains. What…

A: By heating the water is removed from the molecule . From the weight loss we can calculate the…

Q: How many grams of Platinum (Pt) contain the same number of atoms as 5.0g of lithium (Li)

A:

Q: a) How many sulfur atoms are there in 3.8 mol of sulfur? b) How many moles of aluminum do 5.8 X…

A: To get number of atom or molecule from mole number, gram etc, we use Avogadro's number.

Q: Consider 8.63 x 1021 atoms of boron.   How many moles of boron does this represent?

A: 1 mol of atom  = Avogadro's number

Q: How many atoms of Xe does 7.84 moles of Xe contain?

A: 1 mole = 6.022×1023 [ Avogadro's number ] If any element has 6.022×1023 atoms , it is said to have 1…

Q: An unknown compound containing tellurium and bromine is analyzed and it is determined that 28.53% of…

A: According to given data%mass of Tellurium in compound=28.53 %and% mass of Bromine in compound=71.47…

Q: How many atoms of nitrogen are there in 5.00 g N?

A: We have to predict the number of atoms of N.

Q: Given 88.0 grams of Boron, how many atoms of Boron (B) are present

A: To know, number of atoms, first we have to find out number of moles.

Q: How many grams of Xe are there in a sample of Xe that contains 8.97×1023 atoms?

A: First we have to determine the moles of xenon.

Q: How many atoms of calcium are there in 10.0 g of calcium?

A: