overall weight of a molecule = 23*2+12+16*3+10*18=286
weight of H2O per molecule =10*18=180
% H2O =(180/286)100=62.9
The formula given shows that there are ten water molecules consisting of 20 hydrogen atoms and 10 oxygen atoms in the water content of the hydrated salt. The remainder of the formula shows that there are 2 sodium atoms, 1 carbon atom, and 3 oxygen atoms in the remainder of the formula unit.
The gram* atomic masses of the elements involved are: H, 1.00794; C, 12.011; O, 15.9994; and Na, 22.9898. The fraction by mass of water in the hydrated salt therefore is [20(1.00794) + 10(15.9994)]/[20(1.00794) + 10(15.9994) + 2(22.9898) + 12.011 + 3(15.9994)] or 0.62959. The pounds of water in 100 pounds of the hydrated salt therefore is 63.0, to the justified number of significant digits.**
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*Because the question is about proportions, any unit for atomic mass may be used, as long as the unit is consistent for all the atoms involved.
** All of the integers appearing before a left parenthesis in the arithmetic expression given for calculation are exact, but the number of significant digits justified is limited by the value of "100 pounds".
The percentage of water in Na2CO3ยท10H2O is 63.90%.
The chemical formula for sodium carbonate decahydrate, Na2CO3ยท10H2O, indicates that each formula unit of sodium carbonate is associated with 10 water molecules. This specific ratio of water molecules to sodium carbonate ions is due to the way the compound forms and crystallizes in its solid state.
Borax is Na2B4O7·10H2O with a molecular weight of 318.37 g/mol. There are ten water molecules with net molecular weight of 180 g/mol. So the percentage of water = (180 * 100 / 318.37) = 56.56%
No, when calculating the mass of borax needed to make a standard solution, you do not include the water of hydration (such as the 10H2O). You only consider the anhydrous borax (without water molecules) in your calculations.
CaCl2 (Calcium Chloride) 6H2O Na2SO4 (Sodium Sulfate) 10H2O Na2CO3 (Sodium Carbonate) 10H2O Na2HPO4 (Dibasic Sodium Orthophosphate) 12H2O Na2HPO4 (Dibasic Sodium Orthophosphate) 7H2O Na2S2O3 (Sodium Thiosulphate) 5H2O Ba(OH)2 (Barium Hydroxide) 8H2O
The chemical equation for sodium carbonate is Na2CO3. It is made up of two sodium atoms, one carbon atom, and three oxygen atoms. When dissolved in water, it dissociates into sodium ions (Na+) and carbonate ions (CO3^2-).
Na2CO3-10H2O
mass of Na2CO3 with 10H2O of crystallisation is 286g
Na2CO3.10H2O --> Na2CO3 + 10H2O
The chemical formula for sodium carbonate decahydrate, Na2CO3ยท10H2O, indicates that each formula unit of sodium carbonate is associated with 10 water molecules. This specific ratio of water molecules to sodium carbonate ions is due to the way the compound forms and crystallizes in its solid state.
Technically it is a mixture called a hydrate. This particular one is sodium carbonate decahydrate.
A mineral of hydrous sodium carbonate, Na2CO3·10H2O, often found crystallized with other salts.
Borax is Na2B4O7·10H2O with a molecular weight of 318.37 g/mol. There are ten water molecules with net molecular weight of 180 g/mol. So the percentage of water = (180 * 100 / 318.37) = 56.56%
When Na2CO3 (sodium carbonate) is added to water, it dissociates into sodium ions (Na+) and carbonate ions (CO3^2-). The carbonate ions can react with water to form bicarbonate ions (HCO3-) and hydroxide ions (OH-), increasing the pH of the solution. Sodium carbonate is commonly used as a pH buffer and to soften water due to its ability to remove magnesium and calcium ions.
Sodium carbonate x water --> sodium carbonate (in solution)--> Sodium Carbonate Decahydrate
CaCl2 (Calcium Chloride) 6H2O Na2SO4 (Sodium Sulfate) 10H2O Na2CO3 (Sodium Carbonate) 10H2O Na2HPO4 (Dibasic Sodium Orthophosphate) 12H2O Na2HPO4 (Dibasic Sodium Orthophosphate) 7H2O Na2S2O3 (Sodium Thiosulphate) 5H2O Ba(OH)2 (Barium Hydroxide) 8H2O
The solubility of sodium carbonate in water at 20 0C is approx. 22 g Na2CO3/100 g water.
10H2O = 10 H2O so there will be 10 moles of water