Here's my best guess
the volume of the unit cell is (385*10^-12)^3=5.7066*10^-29 m^3
multiply by density to get mass
mass = (7 g/cm^3)*(100^3 cm^3 / 1^3 m^3) * 5.7066*10^-29 m^3= 3.99466*10^-22 g
covert to moles
3.99466*10^-22 g * 1 mol / 239.82 g = 1.6657 *10^-24 mol
convert to number of units
1.6657 *10^-24 mol * 6.23*10^23 units/mol = 1.04
385 pm = 3.85*10^(-8) cm
The volume of the unit cell is the cube of that, which is 5.71*10^(-23) cm^3. Since the ratio of mass to volume (i.e. the density) must be the same no matter what amount of TlCl you have, you can say:
7 = x/(5.71*10^(-23)), where x is the mass of the unit cell. Solving for x, you get 4*10^(-22) g.
The mass of a molecule of TlCl is 240 amu, which in grams is 4*10^(-22) g. The mass of the unit cell and the mass of a molecule of TlCl is the same. Therefore there is one formula unit of TlCl per unit cell.
Answer:
12.7.
Explanation:
∵ pOH = - log[OH⁻].
[OH⁻] = 0.051 M.
∴ pOH = - log[OH⁻] = - log(0.051 M) = 1.29.
∵ pH + pOH = 14.
∴ pH = 14 - pOH = 14 - 1.292 = 12.7.
The molecular formula of a compound having the empirical formula C9H17O is calculated as below
(C9H17O)n =847.56
{(12 x9 + 1 x17 + 1 x16)}n= 847.56
147 n = 847.56
divide bot
h side by 147
n= 6
(C9H17O)6 therefore the molecular formula = C54H102O6
Answer:
E) HBr
Explanation:
Because Bromine (Br) isn't part of the original formula for Apirin. (I answered this based on the assumption that the letter "A" in option C was a typo of sorts, since there is no element with a chemical symbol of just "A" that I am aware of. If this is incorrect, then I apologize.)