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:
121 g/mol
Explanation:
To find the molar mass, you first need to calculate the number of moles. For this, you need to use the Ideal Gas Law. The equation looks like this:
PV = nRT
In this equation,
-----> P = pressure (atm)
-----> V = volume (L)
-----> n = moles
-----> R = constant (0.0821 L*atm/mol*K)
-----> T = temperature (K)
Because density is comparing the mass per 1 liter, I am assuming that the system has a volume of 1 L. Before you can plug the given values into the equation, you first need to convert Celsius to Kelvin.
P = 1.00 atm R = 0.0821 L*atm/mol*K
V = 1.00 L T = 25.0. °C + 273.15 = 298.15 K
n = ? moles
PV = nRT
(1.00 atm)(1.00L) = n(0.0821 L*atm/mol*K)(298.15 K)
1.00 = n(0.0821 L*atm/mol*K)(298.15 K)
1.00 = (24.478115)n
0.0409 = n
Now, we need to find the molar mass using the number of moles per liter (calculated) and the density.
0.0409 moles ? grams 4.95 grams
---------------------- x ------------------ = ------------------
1 L 1 mole 1 L
? g/mol = 121 g/mol
**note: I am not 100% confident on this answer
Answer:
The answer is B
Explanation:
3+ means there is 3 more protons than electrons.
So electron need 3 more (-ve) charge in order to have the same charge as proton to become neutral atom (no charge).
e + 3 = 8
e = 8 - 3
= 5
The pH of the solution is used to estimate the acidic and the alkaline condition. The pH paper can be used to determine the conditions. The compound with pH 13.3 is basic.
<h3>What is pH?</h3>
The concentration of the hydrogen or the hydroxide ion in the water gives the estimate of the pH. The potential and the amount of hydrogen decide the acidic and the basic compound.
The pH scale ranges from 0-14 where the scale of 0-6 is acidic, 7 is neutral and 8-14 is basic. If the substance shows a pH of 13.3 then it will lie in the basic range.
Therefore, the compound with a pH of 13.3 is basic.
Learn more about pH here:
brainly.com/question/15075648
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8.43
58.44g/mol*1/6.93g= 8.43moles of NaCL