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.
The amount of calories you weight
<em>Thermal energy</em> is the sum of the kinetic and potential energies of all the particles in an object.
Assume that you have 250 gL of water and 1 kg of water at the same temperature.
Then, each water molecule has the same kinetic energy.
The larger sample contains four times as many molecules, so it contains four times as much thermal energy.
Thus, thermal energy is directly proportional to mass.
In symbols, <em>KE </em>∝ <em>m</em> or <em>KE = km</em>.
The graph of a direct proportion is a <em>straight line passing trough the origin</em>.
It should look something like the graph below.
Answer: A tropical year is longer than 12 lunar months and shorter than 13 of them. The arithmetical equation
12x12 + 7x13 = 235
allows it to be seen that a combination of 12 'shorter' (12 months) years and 7 'longer' (13 months) years will be equal to 19=12+7 solar years.
Explanation:
