You need to find the whole molar mass of the compound using the periodic table to add the values.
Na2CO3= (2 x 23.0) + 12.0 + (3 x 16.0)= 106 g/mol
H2O= 10 x [ (2 x 1.01 ) + (16.0) ]= 180.2 g/mol
the total molar mass is 106 + 180.2 = 286.2 g/mol
the percentage of water you can find by doing "parts over the whole"
H2O%= 180.2 / 286.2 X 100= 63.0%
Explanation:
Equation for Calcium Hydroxide Dissolving in Water | Ca(OH)2 + H2O
First M stands for Molarity which is (moles of solute) / (Liters of solution). we also know that moles = (mass) / (molar mass). so we can form some equations here. We know:
Molarity (M) = moles (mol) / Liters (L)
moles (mol) = (mass) / (molar mass)
we can substitute the (mass) / (molar mass) for (moles) and get:
M = [(mass) / (molar mass)] / Liters
we can now isolate mass and get
M * Liters * molar mass = mass
now we need to find the molar mass of CaCl2 which is 110.98 g/mol
plug the values in and get
.350M * 6.5L * 110.98 g/mol = mass
mass = 252.4795g however the 6.5L has only 2 sig figs so i would say
mass CaCl2 = 2.5 * 10 ^2 g
c. table salt is a metalloid with properties of both reactants
The frequency of a photon of red light with wavelength 4.50 x 10−7m is 6.67 x 1014Hz
