Answer:
17
Explanation:
the mass number of the element which is protons and neutrons is 17+18=35
electronic configuration is 2, 8, 7
valency of the element is 1 therefore the atomic number is 17
Answer:

Explanation:
Hello there!
In this case, according to the given information, it will be possible for us to solve this problem by using the Boyle's law as an inversely proportional relationship between pressure and volume:

In such a way, we solve for the final volume, V2, and plug in the initial volume and pressure and final pressure to obtain:

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Electron
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~davatar~
Hello!
The molarity of the HBr solution is 0,172 M.
Why?
The neutralization reaction between LiOH and HBr is the following:
HBr(aq) + LiOH(aq) → LiBr(aq) + H₂O(l)
To solve this exercise, we are going to apply the common titration equation:


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