Answer:
number of moles = 0.21120811
Explanation:
To find the number of moles, given the mass of the solute, we use the formula:




Label the variables with the numbers in the problem:



The first thing we have to do is find the molar mass of sodium sulfate, in order for us to use the formula for finding the number of moles:
Formula for finding the molar mass of sodium sulfate:

For the variables and what they mean are below for finding the molar mass of sodium sulfate:





Plug the numbers into the formula, to find the molar mass of sodium sulfate:











Now that we have found the molar mass, we can calculate the number of moles in the solution of sodium sulfate with the formula:








0.21120811 rounded gives you 0.2112
or if you did the problem without decimals
30 grams of sodium sulfate divided by its molecular weight – which we found to be 142 – gives us a value of 0.2113 moles.
Answer:
Blackbody radiation
Explanation:
This phenomenon described by Susan is know as black body radiation. Different materials by color reacts to incident radiation on them in diverse manner.
- A white surface will reflect all the wavelength of light incident on it.
- A black surface will absorb all the wavelength of light on it.
This absorption causes the black surface to be hotter compared to other surfaces.
It is A because it has a lower activation emery than like B
It is 292.5 m because you do 4.5 hours times 65. (please give me brainliest)