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An element crystallizes in a body-centered cubic lattice. The edge of the unit cell is 0.286 nm, and the density of the crystal is 7.92 g/cm3 . Calculate the atomic weight of the element.
The atom weighs 1.85 x 10-²² g.Explanation:So, 0.286 nm = 2.86 x 10-⁸ cm.Also, to get the volume, we have (2.86 x 10-⁸ cm)³ = 2.3393 x 10-²³ cm³.Multiply it...
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Element A has 17 electrons, element B has 19 electrons. Element C has 35 electrons. Which of these elements have the smallest atomic radius
Element A
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15 In chemistry, substances react on the basis of ?
Amount in grams equivalent
Amount in volume equivalent
Amount in relative ratios
Amount in moles equivalent
Amount in moles equivalent The mole is a unit of measurement used in chemistry to express amounts of a chemical substance solution and mole is widely used in chemistry, instead...
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Fictitious element X has an a average atomic mass of 254.9 and only 2 isotopes, One of its isotopes has an abundance of 72.00 and a mass of 250.9 amu. What is the atomic mass of the second isotope?
Solution:The average atomic mass of an element is the sum of the masses of its isotopes, each multiplied by its natural abundance.Average atomic mass = f1M1 + f2M2 +… + fnMn where...
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A single atom of an unknown element weighs 9 x 10 -23g. What is the atomic weight of the element?
One atomic mass unit (amu) equals:1 amu = 1.6605 × 10−24 gFrom here, the atomic mass of the element equals:m(element) = 9 × 10-23 g / 1.6605 × 10−24 g = 5.42...
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An element X reacts with O2 to form a compound X2O5. If 0.35g of the element forms 0.55g of the compound, what is the approximate atomic mass of the element?
Let x be atomic mass of the element X (in grams per mole). Atomic mass of O is known, it is 16. Then molar mass of the compound must be...
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The electron configuration of element X is 1s22s22p63s23p3
i) What is the atomic number of this element?
ii) Identify the element.
The element is P (phosphorus). The atomic number is 15.
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3.011 x 10^22 atoms of an element weight 1.15 gm. What is the atomic mass of the element?
At first, number of moles should be found: n=N/Nan=3.011×1022/6.022×1023=0.05(mol)M=m/n=1.15/0.05=23(g/mol)So, we may assume that this element is Sodium.
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Reacts element A which has 7 electrons on layer 3 with 2 moles of magnesium. Indicate element A, model the magnesium bond and specify the number of protons found in the required amount of element A.
Element A is a Chlorine, he has 7 electrons on 3 layer, and 17 protons. Chlorine is a chemical element with the symbol Cl and atomic number 17. Mg +...
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Element G has a quarter life of 10 hours. If there are 65 grams of element G after the time equivalent to thrce the half-life, how many milligrams of element G are present initially
The half-life of a substance is the time it takes for half of the substance to decay.Initially G = 65 x 2 = 130 g =1.3 x 105 mg
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