Answer:
68,2%
Explanation:
Supposing the initial salt concentration of lake Parsons is the same of non-isolated lakes, 6,67L, and the change of salt concentration in isolated lake is just for water evaporation it is possible to write:
6,67gL⁻¹×X = 21gL⁻¹×Y
<em>-Where X is the initial water and Y is the water that remains in the isolated lake-</em>
Thus:
6,67X = 21Y
0,318 = Y/X
0,318 is the ratio of water that remains between total water. To obtain the ratio of evaporated water:
1-0,318 = 0,682
In percentage: <em>68,2%</em>
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I hope it helps!
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The correct answer is option C, 5.02 x 10²² carbon atoms
Atomic mass of C = 12 g/mol
According to Avogadro, 1 mole of C has 6.023 x 10²³C atoms
Now 1 mole of C is equal to 12 g
Therefore, 12 g of C = 6.023 x 10²³ C atoms
1 g of C =
C atoms = 5.02 x 10²² C atoms
Answer:
1L
Explanation:
First, let us calculate the number of mole present in 20g of NaOH. This is illustrated below:
Mass = 20g
Molar Mass of NaOH = 23 + 16 + 1 = 40g/mol
Number of mole =?
Number of mole = Mass /Molar Mass
Number of mole of NaOH = 20/40 = 0.5mol
From the question given, we obtained the following data:
Molarity = 0.5M
Mole = 0.5mole
Volume =?
Molarity = mole /Volume
Volume = mole /Molarity
Volume = 0.5/0.5
Volume = 1L