To be honest, I learned this in school so I'll tell you XD
The formula of sodium oxide is Na2O
Answer: 66
Explanation: To find the mass number you would have to add the number of protons and the number of neutrons.
<span><span>When you write down the electronic configuration of bromine and sodium, you get this
Na:
Br: </span></span>
<span><span />So here we the know the valence electrons for each;</span>
<span><span>Na: (2e)
Br: (7e, you don't count for the d orbitals)
Then, once you know this, you can deduce how many bonds each can do and you discover that bromine can do one bond since he has one electron missing in his p orbital, but that weirdly, since the s orbital of sodium is full and thus, should not make any bond.
However, it is possible for sodium to come in an excited state in wich he will have sent one of its electrons on an higher shell to have this valence configuration:</span></span>
<span><span /></span><span><span>
</span>where here now it has two lonely valence electrons, one on the s and the other on the p, so that it can do a total of two bonds.</span><span>That's why bromine and sodium can form </span>
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</span>
Answer: Option (d) is the correct answer.
Explanation:
The amount of salt present or dissolved in water or water body is known as salinity.
When salinity increases then number of particles increases, therefore, density will increase. Also, number of ions will decrease thus, electrical conductivity will decrease.
On the other hand, increase in salinity will increase the amount of salt (NaCl) is the water.
Thus, we can conclude that out of the given options, the option all of the above is true.