B I believe. Hope this helps you!
-Belle
There are many ways to predict the properties of an element here's one example.As you move from left to right the electron affinity and ionization energy both increase .Since elements of the same family have similar characteristic,you can often predict the properties of another element in its family
the answer is 17.031 g/mol
Well, the molar mass of acetone would be
3(12.011)+6(1.008)+15.999 , which cleans up to be 58.08 grams.
out of this total, 3(12.011), or 36.033 grams are carbon
So, to find the percent, you do part over whole
36.033/58.08, which equals 0.6204 with significant figures
multiply that by 100 to get 62.04%
Hope that helps!
First, let's assign variables for the moles of CuSO₄·5H₂O as x and moles of MgSO₄·7H₂O as y. The molar mass of the substances are the following
CuSO₄·5H₂O: <span>249.685 g/mol
</span>CuSO₄: <span>159.609 g/mol
</span>MgSO₄·7H₂O: <span>246.49 g/mol
</span>MgSO₄: <span>120.366 g/mol
</span>H₂O: 18 g/mol
The solution is as follows:
2.988 = 249.685x + 246.49y --> eqn 1
5.02 - 2.988 = 18(5x + 7y) --> eqn 2
Solving both equations simultaneously, the values of x and y are:
x = 0.0134 mol CuSO₄·5H₂O
y = 0.0257 mol MgSO₄·7H₂O
Thus, the percent CuSO₄·5H₂O is equal to
Mass Percentage = [(0.0134 mol CuSO₄·5H₂O)*(249.685 g/mol )]/{[(0.0134 mol CuSO₄·5H₂O)*(249.685 g/mol )] + [(0.0257 mol MgSO₄·7H₂O)*(246.49 g/mol)]} * 100
Mass percentage = 34.56%