Answer:
D) CN⁻
Explanation:
Hund's Rule of Maximum Multiplicity state that electrons go into degenerate orbitals of sub-levels (p,d, and f ) singly before pairing commences. Hund's rule is useful in determining the number of unpaired electrons in an atom. As such, it explains some magnetic properties of elements.
An element whose atoms or molecules contain unpaired electrons is paramagnetic. i.e., weakly attracted to substances in a magnetic field.
On the other hand, the element whose atoms or molecules are filled up with paired electrons is known as diamagnetic, i.e., not attracted by magnetic substances.
According to the molecular orbital theory, the diamagnetic molecule is CN⁻ because of the absence of unpaired electrons.
Answer:
Diamond.
Explanation:
Having thermal conductivity of more than 2,000 WMK
WMK = Watts per Meter per Kelvin
Answer:
MOLAR MASS = 32 g/mol
Explanation:
Condition of standard temperature and pressure(STP) are as follow:
Temperature = 273 K
Pressure = 1 atm (or 100000 Pa)
Here atm is atmosphere and Pa is Pascal
STP conditions arte used for measuring gas density and volume using Ideal Gas Law.Here 1 mole of ideal gas occupies 22.4 L of volume.
According toi Ideal Gas Equation :
PV = nRT
where P = pressure, n= number of moles, V = volume ,R= Ideal Gas Constant and T= temperature
![n=\frac{PV}{RT}](https://tex.z-dn.net/?f=n%3D%5Cfrac%7BPV%7D%7BRT%7D)
From question:
V=280 ml = 0.28 L
P = 1 atm
R=0.08205 L atm/K mol
T=273 K
Putting values in above formula :
![n=\frac{1\times .280}{0.08205\times 273}](https://tex.z-dn.net/?f=n%3D%5Cfrac%7B1%5Ctimes%20.280%7D%7B0.08205%5Ctimes%20273%7D)
n = 0.0125 moles
Now ![n=\frac{given\ mass}{Molar\ mass}](https://tex.z-dn.net/?f=n%3D%5Cfrac%7Bgiven%5C%20mass%7D%7BMolar%5C%20mass%7D)
![Molar\ mass=\frac{given\ mass}{n}](https://tex.z-dn.net/?f=%3Cstrong%3EMolar%5C%20mass%3D%5Cfrac%7Bgiven%5C%20mass%7D%7Bn%7D%3C%2Fstrong%3E)
given mass = 0.4 g (given)
![Molar\ mass=\frac{0.4}{0.0125}](https://tex.z-dn.net/?f=%20%3Cstrong%3EMolar%5C%20mass%3D%5Cfrac%7B0.4%7D%7B0.0125%7D%3C%2Fstrong%3E)
On solving we get:
Molar mass = 32 g/mol
Label each statement with its corresponding type of scientific knowledge.
law
theory
fact
hypothesis
The melting point of ice is 0°C: thus is a fact based on repetitive experiments
Repeated observations have consistently
shown that oppositely charged objects
attract each other: this is law
When the elements carbon and nitrogen
are mixed at 1500°C, they will react
with each other.
this is a hypothesis
Atoms are made of protons, neutrons,
and electrons. Although we can’t directly
see these particles, this structure
explains many experimental observations
Theory