Because the chemicals are different
by radiation from the Earth's surface
<u>Answer:</u> The molality of solution is 0.740 m.
<u>Explanation:</u>
To calculate the mass of solvent (water), we use the equation:
Volume of water = 750 mL
Density of water = 1 g/mL
Putting values in above equation, we get:
To calculate the molality of solution, we use the equation:
Where,
= Given mass of solute = 100.0 g
= Molar mass of solute = 180 g/mol
= Mass of solvent (water) = 750 g
Putting values in above equation, we get:
Hence, the molality of solution is 0.740 m.
Answer:
The concentration the student should write down in her lab is 2.2 mol/L
Explanation:
Atomic mass of the elements are:
Na: 22.989 u
S: 32.065 u
O: 15.999 u
Molar mass of sodium thiosulfate, Na2S2O3 = (2*22.989 + 2*32.065 + 3*15.999) g/mol = 158.105 g/mol.
Mass of Na2S2O3 taken = (19.440 - 2.2) g = 17.240 g.
For mole(s) of Na2S2O3 = (mass taken)/(molar mass)
= (17.240 g)/(158.105 g/mol) = 0.1090 mole.
Volume of the solution = 50.29 mL = (50.29 mL)*(1 L)/(1000 mL)
= 0.05029 L.
To find the molar concentration of the sodium thiosulfate solution prepared we use the formula:
= (moles of sodium thiosulfate)/(volume of solution in L)
= (0.1090 mole)/(0.05029 L)
= 2.1674 mol/L
Answer:
Explanation:
Hello,
In this case, a percent composition is computed by considering the atomic mass of each element in the compound as well as the number of atoms and the molar mass of the compound. Thus, Sb2F3 has a molar mass of 300.52 g/mol, antimony has an atomic mass of 121.76 g/mol and fluorine 19.0 g/mol, therefore, the percent composition of fluorine which has three atoms with five significant figures is:
Best regards.