When the nuclear half-life of the radioactive isotope is showing the time needed for the isotope to be half of its initial value of mass.
so with each half-life, the isotope will be halved of its initial value as example:
after the first half-life, the isotope will lose 50 % of its initial value
and after the second half-life, the isotope will lose 25% of its initial value
and after the third half-life, the isotope will lose 12.5 % of its initial value
and so on,
So here to get how many numbers of half-lives we will use this formula:
numbers of half-lives = total time passed / the half-life of the isotope
= 30 days / 14 days
=2 days
∴remainig mass = initial mass / 2^numbers of half-lives
= 10 g / 2^2
= 2.5 g
Answer:
The epipelagic zone reaches from the surface of the ocean down to around 650 feet. This is the zone most exposed to light, and as such is host to the highest concentrations of the ocean's life. There are thousands of animals that roam this zone, including dolphins, most sharks, jellyfish, tuna and corals.
(From Internet I’m being honest)
1/4 Ao = Ao * ( 1/2)^(t/106)
t = 212
subtract 4.6 billion years
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Answer:
A hydrogen bonding is a bond class that is produced from the attraction existing in a hydrogen atom and an oxygen, fluorine or nitrogen atom with a negative charge. This attraction, meanwhile, is known as dipole-dipole interaction and links the positive pole of one molecule with the negative pole of another.
Explanation:
The hydrogen atom, which has a positive charge, is known as the donor atom, while the oxygen, fluorine, chlorine or nitrogen atom is the bond acceptor atom. In the substance in which they are most effective is in the water.
Hydrogen bonds have only one third of the strength of covalent bonds, but they have important effects on the properties of the substances in which they occur, especially in terms of melting and boiling points in crystal structures.
