Calculate concentration of solutions:

2.86 g Sodium Carbonate crystals

Na2CO3.10H2O dissolved in 250 cm^3 of solution

To calculate the concentration of a solution, we need to first determine the amount of solute (in this case, Sodium Carbonate crystals) and the volume of the solution.

Given:
Amount of Sodium Carbonate crystals = 2.86 g
Volume of solution = 250 cm^3

To calculate the concentration, we need to convert the given values to the same unit. Let's convert the volume from cm^3 to liters (L) since the standard unit for concentration is moles per liter (mol/L).

1 cm^3 = 0.001 L
250 cm^3 = 250 x 0.001 L = 0.25 L

Next, we need to calculate the number of moles of Sodium Carbonate using its molar mass. The molar mass of Na2CO3.10H2O can be calculated by adding up the atomic masses of the individual elements in the compound:

Na2CO3: 2(Na) + (C) + 3(O) = 2(23) + 12 + 3(16) = 46 + 12 + 48 = 106 g/mol
10H2O: 10(2)(1) + 10(16) = 20 + 160 = 180 g/mol

Total molar mass of Na2CO3•10H2O = 106 g/mol + 180 g/mol = 286 g/mol

Now, we can calculate the number of moles of Sodium Carbonate dissolved in the solution:

Number of moles = mass / molar mass
Number of moles = 2.86 g / 286 g/mol = 0.01 mol

Finally, we can calculate the concentration of the solution:

Concentration (in mol/L) = number of moles of solute / volume of solution
Concentration = 0.01 mol / 0.25 L = 0.04 mol/L

Therefore, the concentration of the Sodium Carbonate solution is 0.04 mol/L.

M = mols/L solution.

mols Na2CO3.10H2O = grams/molar mass = ?
Then M = mols/0.250 = ?
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