After 0.69 g of CoCl2⋅6H2O is heated, the residue has a mass of 0.333 g . Calculate the % H2O in the hydrate.
[(0.69 g-0.333g)/0.69g]×100=????
2 sig figs
and .....hat was the actual number of moles of water per formula unit CoCl2
To calculate the percent of water in the hydrate, we need to determine the mass of water lost during heating and divide it by the initial mass of the hydrate, then multiply by 100.
First, calculate the mass of CoCl2 in the hydrate:
Mass of CoCl2 = Mass of hydrate - Mass of water
Mass of CoCl2 = 0.333 g - 0.69 g = -0.357 g
Since the mass of CoCl2 cannot be negative, it means there was an error in the calculations.
Please double-check the values provided for the mass of the hydrate and the mass of the residue after heating.
To calculate the percentage of water in the hydrate, we need to determine the mass of water and the mass of the anhydrous compound.
Given data:
Initial mass of the hydrate = 0.69 g (CoCl2⋅6H2O)
Mass of the residue after heating = 0.333 g
To find the mass of water, subtract the mass of the residue from the initial mass of the hydrate:
Mass of water = Initial mass of the hydrate - Mass of the residue after heating
= 0.69 g - 0.333 g
= 0.357 g
Now, we can calculate the percentage of water in the hydrate using the formula:
% H2O = (Mass of water / Initial mass of the hydrate) × 100
Substitute the known values into the formula:
% H2O = (0.357 g / 0.69 g) × 100
Calculating this expression will give us the percentage of water in the hydrate.