Noble gases show degrees of reactivity. These elements have generally complete electron shells. Noble Gases Include: Helium, Neon, Argon, Krypton, Xenon, Radon, Ununoctium. Reactive elements that form compounds known as halides.
Answer:
1...option B
2... peroids
3..group
4.. metals
5...7
6...dmitri mendeleev
7.. xenon
8... compound can be broken down by physical means
9... they can be broken down into simpler substance
sry if its wrong
last two 8th and 9th i do t think ots correct
Answer:
Explanation:
The charges are as follows:
since oxidation number of lead is 2 as indicated lead (II)nitrite. The number in parentheses indicates the oxidation number.
bears the charge -1.
As lead bears 2 positive charges so we need two nitrite ions to form lead (II) nitrite.
, it is a halogen and bears the charge -1.
, it is an alkali metal.
Since Bromide bears -1 charge and potassium bears +1 charge so we need only 1 ion of bromide and 1 ion of potassium to form potassium bromide.
Similarly, to form lead bromide we need 2 ions of bromide and 1 ion of lead, and to form potassium nitrite we need 1 nitrite ion and 1 potassium ion.
The final balanced equation is as follows, the various states of reactants and products are also written properly.
Half-life is the amount of time, in days or years( most common) a certain substance disintegrate half of it's content.
We are given the initial (Ao) and final (A) amount of the substance. The time passed (T) is also given and we are asked to find the half-life (t). We use the equation below:
A=Aoe^(-ln2/t)T
25=200e^(-ln2/t)(11.46)
Solve for t
Answer: 3.82 days
It's an instrument used for measuring ionizing radiation used widely in applications such as radiation dosimetry