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mestny [16]
3 years ago
5

What is the half-life of Technetium-99 if a 200 gram sample decays to 50 grams in 639,000 years?

Chemistry
1 answer:
Elenna [48]3 years ago
5 0

Answer:

The half-life of Th-232 is 1.4 ∙ 10¹⁰ years.

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An ionic bond can be formed when one or more electrons are
xz_007 [3.2K]

Answer:

Are transferred completely from the valence shell of an element to the other

Explanation:

Basically, to form a chemical bond, you either transfer or you share. When you share, it is a case of covalent bonding which can be in several other forms. When there is a transfer, it is a case of ionic bonding.

The basic explanation for this is that while some atoms are electronically sufficient, some are electronically deficient. This means while some atoms are having an excess number of electrons, then some are having less number of electrons.

To satisfy both parties, there must be a transfer if electrons between the two parties. While the one with the excess numbers serves as the donor, the one with insufficient number of electrons serve as the acceptor

8 0
3 years ago
What is the term for the number of protons in the nucleus of each atom of an element?
xxTIMURxx [149]

Answer:

atomic number

Explanation:

atomic number is the number of protons

5 0
2 years ago
Nitrogen - 14.0067
alina1380 [7]

Answer:

potasium to erbium

Explanation:

3 0
3 years ago
Why aluminum in 1820 had more value than gold​
bonufazy [111]

Answer:

Aluminum had more value than gold in the 1820s, because it was harder to obtain. Hope this helped :)

4 0
3 years ago
Anthracite coal d) is the most abundant grade of coal e) is very soft and burns at high temperatures a) causes the most air poll
forsale [732]

Answer: The correct option is C ( is very hard and burns cleanly).

Explanation:

COAL is a form of rock that is made up of mostly carbon amongst other elements which includes sulphur, nitrogen, hydrogen and oxygen. There are different types of coal which include:

--> anthracite ( 90% carbon)

--> bituminous coal ( 70-90% carbon)

--> lignite ( 60- 70% carbon) and

--> peat (60 % carbon).

Anthracite is the type of coal that contains the highest carbon content ( 90% carbon). This makes it very hard and is often a times referred to as HARD COAL. Anthracite is a higher quality coal for domestic and open fire heating. This is because it contains less impurities than other type of coal and thereby making it to BURN CLEANLY avoiding atmospheric pollution.

6 0
3 years ago
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