Two precursor alkenes
H₃C CH₃
I I
H₂C=C-CH-CH₃ 2,3-dimethyl-1-butene
H₃C CH₃
I I
H₃C-CH=CH-CH₃ 2,3-dimethyl-2-butene
alkane
H₃C CH₃
I I
H₃C-CH-CH-CH₃ 2,3-dimethylbutane
H₃C CH₃ H₃C CH₃
I I I I
H₂C=C-CH-CH₃ + H₂ → H₃C-CH-CH-CH₃
H₃C CH₃ H₃C CH₃
I I I I
H₂C-C=CH-CH₃ + H₂ → H₃C-CH-CH-CH₃
Answer:

Explanation:
Given that:
The Half-life of
=
is less than that of 
Although we are not given any value about the present weight of
.
So, consider the present weight in the percentage of
to be y%
Then, the time elapsed to get the present weight of
= 
Therefore;

here;
= Number of radioactive atoms relating to the weight of y of 
Thus:

--- (1)
However, Suppose the time elapsed from the initial stage to arrive at the weight of the percentage of
to be = 
Then:
---- (2)
here;
= Number of radioactive atoms of
relating to 3.0 a/o weight
Now, equating equation (1) and (2) together, we have:

replacing the half-life of
=
( since
)
∴

The time elapsed signifies how long the isotopic abundance of 235U equal to 3.0 a/o
Thus, The time elapsed is 
number 5 is 1 : 1
number1 is also 1:1 ibelieve but it could be 2:1 just like number 5 but im postive its 1:1 for nummer 1 and number 5
It is a covalant bond. Because any compound made up of nonmetals will be covalant. Compounds made up of a non metal and metal willl form a ionic compund. :)
Stalactites and stalagmites form as ________ precipitates out of the water evaporating in underground caves.
Group of answer choices
hydrochloric acid
sodium bicarbonate
calcium carbonate
sodium chloride
sodium hydroxide
Answer:
calcium carbonate
Explanation:
A stalactite is an icicle-looking mould that is formed by the precipitation of natural minerals as a result of water dripping from the ceiling, hanging from a cave.
A stalagmites in the other hand, grows upwards and is also a mound that is formed by the deposits of minerals gotten by the water dripping on the floor of a cave.
Therefore, stalactites and stalagmites form as calcium carbonate precipitates out of the water evaporating in underground caves.