The best way to accurately determine the pair with the highest electronegativity difference is by using their corresponding electronegativity values. For the each of the choices, the difference is:
A. H-S = 2.5 - 2.1 = 0.4
B. H-Cl = 3 - 2.1 = 0.9
C. N-H = 3 - 2.1 = 0.9
D. O-H = 3.5 - 2.1 = 1.4
E. C-H = 2.5 - 2.1 = 0.4
As show, D. has the highest difference. Without looking at their values, you can also determine the pair with the highest difference by taking note of the trend of electronegativity on the periodic table. Electronegativity increases as you go right a group and up a period. This makes oxygen the most electronegative element among the other elements paired with hydrogen.
The average molecular weight of the mixture can be calculated using this formula:
MWav = x1MW1 + x2MW2
Where x is the mass fraction of the components of the mixture, in this case, copper (63.546 g/mol) and zinc (<span>65.38 g/mol).
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x1 = 7.36 / (7.36+0.51)=0.935
x2 = 0.51 / (7.36+0.51)=0.065
So,
MWav = 0.935(63.546) + 0.065(65.38) = 63.665 g/mol
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:
mass ( g ) = 348 g
Explanation:
First you know : M = mole / volume (L)
in question you have the M and V and the formula of SUBSTANCE ( KF )
first you get the number of mole from equation above
so 3 = no of mole / 2
no of mole = 3 × 2 = 6 moles
and the moles equation is no of moles = mass ( g ) / molecular weight ( g/mole )
so you have already calculate the moles and you can know the MW from the Question
Mw of KF = 39 + 19 = 58
so n = mass / MW
so 6 = mass / 58
mass ( g ) = 348 g
GOOD LUCK
