Answer:
16.8%
Explanation:
31% NaOH molar mass 40 gm
69% H2O molar mass 18 gm
1000 gm would be
310 gm NaOH or 310/40 = 7.75 moles
690 gm of H2O or 690/18 = 38.333 moles
7.75 / (7.75 + 38.333) = .168 mole fraction
Answer:
1.5057×10^22 atom
Explanation:
As we
1 mole of argon = 40 g of argon
i.e 40 g of argon = 1 mole of argon
1 g of argon = 1/40 mole of argon
1 mole of argon = 6.023×10^23 atom of argon
1/40 mole if argon = 1/40 ×6.023×10^23
= 1.5057×10^22
The answer is 6.88.
Solution:
We can calculate for the percent composition of CaCl2 by mass by dividing the mass of the CaCl2 solute by the mass of the solution and then multiply by 100. The total mass of the resulting solution is the sum of the mass of CaCl2 solute and the mass of water solvent. Therefore, the percent composition of CaCl2 by mass is
% by mass = (mass of the solute / mass of the solution)*100
= mass of solute / (mass of the solute + mass of the solvent)*100
= (27.7 g CaCl2 / 27.7g + 375g) * 100
= 6.88
The masses are always equal. Since matter can not be created nor destroyed, you will have the same amount of mass as you did before the reaction as you do after.