Answer:
edge length = 3.61 cm
Explanation:
Givens
m = 369 gm
d = 7.86 gm / cm^3
v = ?
Formula
v = m / d
Solution
v = 369 / 7.86
v = 46.95 cm^3
============
That's not the answer. You must take the cube root of the volume
side = cube root (46.95)
side = 3.61 cm
4.48
pH=pKa+log([A-/HA])
25% deprotonated tells us that A- is .25 and that the rest (75% is protonated) thats .75.
4 = pKa + log \frac{.25}{.75}
4 - log \frac{.25}{.75} = pKa
4.48=pKa
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
