First, let's start off by finding the mass of this whole hydrate.
(Note: the unit of measurement for mass will be amu)
Let's find the molecular mass of each element.




Now, let's find the mass of each compound.


We have 6 molecules of H2O, so multiply 18.015 by 6 then add that with the weight of CoCl2.


Now divide 108.09 (mass of all the H2O in the hydrate) by 237.923 (total mass of hydrate).


Turn that into a percentage and you get 45.431%.
Hope this helps! :)
C. both a and b
If a light bulb can last longer with the same amount of energy it is given, that means it can use less energy to do the same job compared to one that does not last longer with the same amount of energy it is given. It is much like how a more fuel efficient car will be able to go farther on the same tank of gas, but if you pair it with a car that doesn't have as great of an mpg, when they go the same distance, the car with the greater mpg spends less fuel.
If you don't have to use the energy when you aren't utilizing it, then you can conserve the energy for when you do need it.
<span>An unsaturated solution is one that has a concentration lower than it's solubility. What happens is all of the solute dissolves in the solvent. For example, dumping a spoon of sugar into coffee ends up with an unsaturated solution. Because all the sugar dissolves into the solvent (the coffee).</span>