There are six electrons in the covalent bonds.
Two N atoms would be :N:· + ·:N:
An N₂ molecule would be :N:::N: or :N≡N:
This gives each N atom an octet of eight electrons in its valence shell.
It would take 147 hours for 320 g of the sample to decay to 2.5 grams from the information provided.
Radioactivity refers to the decay of a nucleus leading to the spontaneous emission of radiation. The half life of a radioactive nucleus refers to the time required for the nucleus to decay to half of its initial amount.
Looking at the table, we can see that the initial mass of radioactive material present is 186 grams, within 21 hours, the radioactive substance decayed to half of its initial mass (93 g). Hence, the half life is 21 hours.
Using the formula;
k = 0.693/t1/2
k = 0.693/21 hours = 0.033 hr-1
Using;
N=Noe^-kt
N = mass of radioactive sample at time t
No = mass of radioactive sample initially present
k = decay constant
t = time taken
Substituting values;
2.5/320= e^- 0.033 t
0.0078 = e^- 0.033 t
ln (0.0078) = 0.033 t
t = ln (0.0078)/-0.033
t = 147 hours
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Birds use the magnetic fields and some fish i believe as well and maybe butterflies im not entirely sure <span />
Ionic bonds are formed when a cation and an anion transfer electrons. The anion gains electrons from the cation to finish its shell, and is usually a nonmetal or a metalloid. A cation gives the anion its electrons to get rid of its partial shell. Cations are metals.
The molecule is stable and can exist even though the number of valence electrons around central atom in the molecule are less than 8.
<h3>Is BF3 molecule stable or not?</h3>
BF3 molecule is a stable molecule because all the electrons present in the outermost shell of boron are covalently bonded with fluorine. Boron in BF3, three bonds is the maximum possible because boron only has 3 electrons to share.
So we can conclude that the molecule is stable and can exist even though the number of valence electrons around central atom in the molecule are less than 8.
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