Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
The hybridization for C in acetylene, HCCH, or C₂H₂ is 'sp'.
Discussion:
There are three different forms of hybridization -
- sp- The first occurs when two carbon atoms are triple linked.
- sp₂- When two carbon atoms are double-bonded to one another, this is known as sp₂.
- sp₃- When a single bond joins two carbon atoms, this is known as sp₃.
In the case of acetylene(HCCH or C₂H₂):
- The carbon atom requires additional electrons to establish four bonds with hydrogen and other carbon atoms in the synthesis of C₂H₂. One 2s₂ pair is consequently transferred to the vacant 2pz orbital. Each carbon has two sp hybrid orbitals after the 2s orbital in each atom combines with one of the 2p orbitals.
- As a result of the atoms' symmetrical alignment in a single plane, C₂H₂ possesses a linear molecular structure. Due to their lower electronegative nature than Hydrogen atoms, all Carbon atoms are situated near the center of the Lewis structure of C₂H₂.
H-C≡C-H
Therefore, it is concluded from the above discussion that the hybridization type of acetylene is 'sp'.
Learn more about hybridization here:
brainly.com/question/14140731
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Solution..
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Let's calculate the mass of CO₂.
We have (12+(16*2))
= 12+32
=44gmol¯¹..
a. What is the percent by mass of carbon?
Mass of carbon /mass of CO₂ × 100%
12/44 × 100%
=27.3%...
b. What is the percent by mass of oxygen?
Mass of oxygen/mass of CO₂ × 100%
(2×16)/44 × 100%
32/44 × 100%
=72.7%....
To check.. You'll add this two percentage compositions together and see of it gives 100%... If it does then we're good...
27.3%+72.7% = 100%.... Checked..
Hope this helped....?
Answer:
The tissue cells
Explanation:
I think you mean this

It all starts from Carbondioxide. This Carbondioxide is dissolved in the blood and taken by red blood cell and converted into carbonic acid. It then dissociates to form a bicarbonate ion
and a hydrogen ion 
This <--> means that the whole process is reversible. It is a buffer system to maintain the pH in the blood and duodenum. And also to support proper metabolic function.
The atomic number of an element is the same as the number of protons. As long as the atom is neutral, your electrons and protons will be the same number. To find neutrons, you subtract the atomic number from the mass number.
mass number - atomic number = number of neutrons