Write the formula of the compound.
Write the numbers of each atom in the formula. Insert the relative atomic mass for each type of atom. Calculate the total mass for each element.
Add up the total mass for the compound.
Saliva's buffering capacity and flow of secretion are directly related to the rate and extent of demineralization. ... Saliva can act as a replenishing source and inhibit tooth demineralization during periods of low pH, while promoting tooth remineralization when the pH returns to a neutral state.
Answer is: the approximate freezing point of a 0.10 m NaCl solution is -2x°C.
V<span>an't
Hoff factor (i) for NaCl solution is approximately 2.
</span>Van't Hoff factor (i) for glucose solution is 1.<span>
Change in freezing point from pure solvent to
solution: ΔT = i · Kf · m.
Kf - molal freezing-point depression constant for water is 1,86°C/m.
m - molality, moles of solute per
kilogram of solvent.
</span>Kf and molality for this two solutions are the same, but Van't Hoff factor for sodium chloride is twice bigger, so freezing point is twice bigger.
Answer: 1.5 x 10^24
Explanation: Just multiply 2.5 by avagadro's number 6.2 x 10^23 to get the answer.
First you need to calculate the molar mass of H2O. To do that, look at the periodic table and add up the AMUs (atomic mass units)
H = 1.01
O = 16.0
1.01 • 2 + 16.0 = 18.02
Next, use stoichiometry to convert grams into moles. To do that, divide 814.504g by the number of grams in one mole of H2O.
814.504 ÷ 18.02 = 45.2 moles
There are 45.2 moles in 814.504 grams of H2O.
