For an aqueous solution of MgBr2, a freezing point depression occurs due to the rules of colligative properties. Since MgBr2 is an ionic compound, it acts a strong electrolyte; thus, dissociating completely in an aqueous solution. For the equation:
ΔTf<span> = (K</span>f)(<span>m)(i)
</span>where:
ΔTf = change in freezing point = (Ti - Tf)
Ti = freezing point of pure water = 0 celsius
Tf = freezing point of water with solute = ?
Kf = freezing point depression constant = 1.86 celsius-kg/mole (for water)
m = molality of solution (mol solute/kg solvent) = ?
i = ions in solution = 3
Computing for molality:
Molar mass of MgBr2 = 184.113 g/mol
m = 10.5g MgBr2 / 184.113/ 0.2 kg water = 0.285 mol/kg
For the problem,
ΔTf = (Kf)(m)(i) = 1.86(0.285)(3) = 1.59 = Ti - Tf = 0 - Tf
Tf = -1.59 celsius
The air pressure. the air pressure increases as the altitude an object is at increases.
A. Acids increase the number of OH- ions in a solution. FALSE
B. Bases increase the number of OH- ions in a solution. TRUE
C. Acids increase the number of H+ ions in a solution. TRUE
D. Bases increase the number of H+ ions in a solution. FALSE
Answer:
1.138158E24 atoms or 1.14 x 10^24 atoms
Explanation:
To find atoms/particles from moles you just want to convert using avogadro's number which is 6.022 x 10^23
1.89 mol x 6.022 • 10^23
———— = 1.138158E24 atoms
1 mol
so 1.138158E24 atoms or 1.14 x 10^24 for scientific notation
hope this helps :)
