in the star wars series, the death star is a spherical space station and weapon with a diameter of 99 miles. if we had a solid iron sphere with a diameter 6.23 times as large as the death star's diameter, how many iron atoms would be needed to construct such a sphere? (diron = 7.874 g/cm3) ( vsphere = 4/3 π r3 ) do not include units

Q: A mass of 145 g of a certain element is known to contain approximately 3.64 x1024 atoms. What is the…

A: Let the molecular weight of the element is M gm/mol.  Moles = weight/mol. wt.  Or, moles = 145/M  We…

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

A:

Q: When a solid dissolves in water, heat may be evolved or absorbed. The heat of dissolution…

A:

Q: What is the radius (in cm) of a pure copper sphere that contains 1.14 * 1024 copper atoms? [The…

A: Given information:

Q: An element X occurs as three stable isotopes: X-21, X-22 and X-23. X-21 is 90.48% abundant and X-22…

A: Given : Element X exists as three stable isotopes. The three isotopes are: X-21 X-22 X-23

Q: S Ina 3.7-gram sample, there are (A) 1.1 x 10 atoms of gold (B) 3.2 x 1025 atoms of gold (C) 4.4 x…

A:

Q: An experiment requires that enough C,H1206 be used to yield 11.7 g of oxygen. How much C,H1206 must…

A: Given : mass of oxygen, O2 to be yielded = 11.7 g Molar mass of O2 = 32 g/mol Since mass = moles X…

Q: The organophosphate nerve agent A-234 is believed to have the formula C5H8F2NO3P. It is one of the…

A: Molecular formula: C5H8F2NO3P Isotope of organophosphate nerve agent with molecular formula…

Q: Some brands of salami contain 0.090% sodium benzoate (NaC2H3O2) by mass as a preservative. If you…

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: What is the radius (in cm) of a pure copper sphere that contains 1.27*1-^24 copper atoms?  The…

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: 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: A 45.62-gram sample of calcium hydrogen sulfate [Ca(HSO4)2] would contain how many total atoms? Is…

A: Answer:- This question is answered  by using the simple concept of calculation of total number atoms…

Q: None

A: Step 1: Calculation of the molar mass of compound Given,molar mass of X = 5.09 g/mol molar mass of Z…

Q: What are the basic units-single atoms, molecules, or for- mula units-that compose each substance?…

A: Since we only answer up to 3 sub-parts, we’ll answer the first 3. Please resubmit the question and…

Q: Iron exists in nature as a mixture of predominantly three isotopes: ⁵⁴₂₆Fe (53.94 amu), ⁵⁶₂₆Fe…

A: We have to calculate the percentage of rarest of three isotopes.

Q: A pure copper sphere has a radius 0.944 in. How many copper atoms does it contain? [The volume of a…

A:

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

A:

Q: Common brass is a copper and zinc alloy containing 37.0% zinc by mass and having a density of 8.48…

A: Here we have:Volume of common brass = 115.0 cm3Density of common brass = 8.48 g/cm3As we know:

Q: Titanium has five common isotopes: 46 Ti (8.0%), 47 Ti (7.8%), 48Ti (73.4%),49Ti (5.5%), 50Ti…

A:

Q: If the density of lead is 11.34 g / a.m., how many atoms are there in a piece of lead 2.5 cm wide,…

A: To calculate the number of atoms in the sample, we must have the number of moles of the substance.…

Q: An unknown element X has the following isotopes: 1ºX (20.00% abundant, atomic mass = atomic mass =…

A:

Q: An unknown element X has the following isotopes: 126X (22.00% abundant), 128X (34.00% abundant),…

A: These are three isotopes of element X are given .Calculate the average atomic mass of X in…

Q: An unknown element X has the following isotopes: ²⁵X (80.50% abundant, mass = 25.03 amu) and ²⁷X…

A:

Q: What fraction of the a particles in Rutherford’s gold foil experimentare scattered at large angles?…

A: The cross-sectional area occupied by the nucleus as a fraction of that occupied by the atom can be…

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: When iridium-192 is used to treat cancer, a small cylindrical piece of 192Ir, a 0.6 mm in diameter…

A: Given,

Q: [The volume of a sphere is (4/3)πr3 and the density of copper is 8.96 g/cm3.] A pure copper sphere…

A: Number of atoms in a mole of any substance is equal to Avogadro's number.

Q: Boron and sulfur form two binary compounds. The first contains 0.2247 g B/1.000 g S, and the second…

A: Atomic Mass of B - 10.811 u Atomic Mass of S - 32.065 u Given, For the second compound 0.1348 g…

Q: What is the mass of a mole of electrons if one electronhas a mass of 9.11 × 1 0 -28 g?

A: Because, 1 mole=6.022×1023 molecules/particles Therefore, 1 mole of electron=6.022×1023 electrons

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: 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: The compound, X,03, contains element .5 X and oxygen atom combined in a ratio of 2.17 grams of X to…

A: The mass ratio of atom X to oxygen in X2O3 is = 2.17: 1 In the second compound, the mass ratio of…

Q: How many atoms are contained in a block of aluminum metal measuring 4.0 mm x 9.0 mm x 11 mm? The…

A:

Q: How many atoms are contained in a block of aluminum metal measuring 8.0 mm x 6.0 mm x 15 mm? The…

A: Given, length of aluminum block = 8.0 mm = 0.8 cm                            ( since 1 mm = 0.1 cm)…

Q: What would the mass be of Gold, if you had 6.02 x 10^24 atoms of

A: GOLD, molar mass of Au = 196.97 g/mol atoms of Au = 6.023 x 1023

Q: What is the mass of 3.50 billion billion atoms of rhenium?  (One billion billion is 1 x 10^18)

A: Given: The number of atoms of Rhenium(Re)=3.50×1018  The atomic mass of Re=186.207 u

Q: 7. H₂O + CaO Ca(OH)2 (HINT: Don't forget to multiple the atoms by the number outside their…

A: For balancing the equation, first balance the elements that appear only once on each side of the…

Q: A pure copper cube has an edge length of 2.76 cm How many copper atoms does it contain? (volume of…

A: Density of a unit cell is given by, Density = Z×Ma3×NA where, Z is the number of atoms in the unit…

Q: The density of copper is 8.96 g/cm3. How many copper atoms are in a sphere with a volume of 0.475…

A: Mass = Volume x density Number of moles = Mass in gram/Molar mass Number of atoms = Number of moles…

Q: The water found on Earth is almost entirely made up of the 'H and 160 isotopes for a formula of H2O…

A: The element which contains the same number of protons and different number of neutron is known as…

Q: estion 4: Fill in the blanks with the suitable concept: The process due to which chemical changes…

A: Answer: 1) Electrolysis : The process due to which chemical changes take place by passing electric…

Q: Q1. a- Please calculate, how many atoms exist in 1 cm^3 of Copper (Cu) with the density 8,93 gr /…

A: denisty of Cu = 8.93 g/cm3 Therefore in 1cm3 of volume 8.93 g of copper has been occupied(8.93 g /…

Mole Concept

Mole concept is a method to determine the amount of any substance that consists of some elemental particles using a grouping unit called ‘mole’. The mole concept enables one to handle the large amount of small elementary particles. The mole concept can be used in many calculations related to mole calculation, molar amount, mole ratio, and so on, which are significant in chemistry.