The valence of lead is 4.
Hence the name of the compound is called Lead (IV) oxide.
<h3>Further explanation</h3>
Given
PbO₂ compound
Required
The valence of Pb
Solution
The oxidation number of element O in the compound = -2, except for OF₂ the oxidation state = + 2 and the peroxides (Na₂O₂, BaO₂) the oxidation state = -1 and superoxide, for example KO₂ = -1/2.
The oxidation state in the uncharged compound = 0,
So The oxidation state of Pb :
Pb + 2.(-2) = 0
Pb - 4 = 0
Pb = +4
Answer: Three samples that can be used to test for poisons are blood samples, hair samples, and gastric contents samples.
Advantages of hair samples area is that it can indicate past exposure to toxins or poisons and also provide information on how long the exposure has been going on. Poisons can sometimes be detected in hair for long periods of time. The advantages of gastric contents samples area is it shows whether the poison was digested or not. An advantage of blood samples is that it’s the most useful toxicological samples. The disadvantage of hair samples is that the results can be tainted by external sources. The disadvantage of gastric content samples is that it doesn’t always show which toxin was digested. The disadvantage of blood samples is if taken near or from the heart it may have artificially high levels of toxins that wouldn’t reflect the amount distributed throughout the body at the time of death.
Explanation:
Answer:
The question is incomplete.(not enough data provided).
Explanation:
a) 1 mole of Ne
b) i/2 mole of Mg
c) 1570 moles of Pb.
d) 2.18125*10^-13 moles of oxygen.
Explanation:
The number of moles calculated by Avogadro's number in 6.23*10^23 of Neon.
6.23*10^23= 1/ 6.23*10^23
= 1 mole
The number of moles calculated by Avogadro's number in 3.01*10^23 of Mg
3.2*10^23=1/6.23*10^23
= 1/2 moles of Pb.
Number of moles in 3.25*10^5 gm of lead.
atomic weight of Pb=
n=weight/atomic weight
= 3.25*10^5/ 207
= 1570 moles of Pb.
Number of moles 4.50 x 10-12 g O
number of moles= 4.50*10^-12/16
= 2.18125*10^-13 moles of oxygen.
