Answer: “We live on a hunk of rock and metal that circles a humdrum star that is one of 400 billion other stars that make up the Milky Way Galaxy which is one of billions of other galaxies which make up a universe which may be one of a very large number, perhaps an infinite number, of other universes. That is a perspective on human life and our culture that is well worth pondering.”
― Carl Saga
Is this it mate?
Answer:
The element will be 
Explanation:
Given that,
Number of proton = 80
Number of neutron = 81
Number of electron = 79
We know that,
The atomic number is equal to the number of proton.
So, the atomic number is 80.
According to atomic number,
The element will be mercury.
We need to calculate the atomic mass
Using formula of atomic mass

Put the value into the formula


We need to find the element
Using atomic mass and atomic number


So, the element will be

Put the value of A and Z
Hence, The element will be 
Uses for radioactive tracers is to look for flaws in metal objects and are also used by doctors to x-ray images to look at your bones.
Answer:
392 g
Explanation:
The given concentration tells us that<em> in 100 g of solution, there would be 15.3 g of 2-ethyltoluene</em>.
With that in mind we can<u> calculate how many grams of solution would contain 60.0 g of 2-ethyltoluene</u>:
- Mass of solution * 15.3 / 100 = 60.0 g 2-ethyltoluene
<span>The gaseous mixture contains 414.0 torr of h2(g), 345.7 torr of n2(g), and 80.1 torr of ar(g). Then, total pressure of the gas would be: 414 torr + 345.7 torr + 80.1 torr= 839.8 torr
The mole fraction of each gas:
H2= 414 torr/</span>839.8 torr= 0.49
N2= 345.7 torr/839.8 torr= 0.41
Ar= 80.1 torr/839.8 torr= 0.10