The question is incomplete, the complete question is;
The Lewis representation above depicts a reaction between hydrogen (blue) and a main-group element from group______ (red).
In this representation, each Y atom needs ______ electron(s) to complete its octet, and gains these electrons by forming______ bond(s) with atoms of H .
There are ______ unshared electron pair(s) and _______bonding electron pair(s) in the product molecule.
The bonds in the product are _________ (Ionic or Covalent)
Answer:
1) 16
2) 2 electrons
3) 2 bonds
4) 2 unshared pairs of electrons
5) 2 bonding pairs of electrons
6) The bonds in the product are covalent
Explanation:
Group sixteen elements have six electrons on their outermost shell. These include two unshared pairs of electrons and two unpaired electrons. These two unpaired electrons can now be covalently bonded to two hydrogen atoms to give H2Y. The compound H2Y has two lone pairs and two bond pairs of electrons.
H2Y can be a general formula for all hydrides of group 16. They are all very similar in structure but gradually differ in physical and chemical properties according to the graduated variation observed down the group.
Density= mass/volume
= 100/25
density = 4g/ml
Answer:
Diameter He = 0,1 nm.
Explanation:
Km to nm:
⇒ Diameter He = 1.0 E-13 Km * ( 1000 m / Km ) * ( 1 E9 nm / m )
⇒ Diameter He = 0.1 nm
Answer:
pH = 8.34
Explanation:
The equilbriums of the amphoteric HCO₃⁻ (Ion of NaHCO₃) are:
H₂CO₃ ⇄ <em>HCO₃⁻</em> + H⁺ Ka1 <em>-Here, HCO₃⁻ is acting as a base-</em>
<em>HCO₃⁻</em>⇄ CO₃²⁻ + H⁺ Ka2 <em>-Here, is acting as an acid-</em>
Where Ka1 = 4.3x10⁻⁷ and Ka2 = 4.8x10⁻¹¹. As pKa = -log Ka:
pKa1 = 6.37; pKa2 = 10.32
As the pH of amphoteric salts is:
pH = (pKa1 + pKa2) / 2
<h2>pH = 8.34</h2>
