Answer:
gain or loses electrons.
Explanation:
Because the atom need to be balanced.
Answer:
2.15 mg of uranium-238 decays
Explanation:
For decay of radioactive nuclide-

where N is amount of radioactive nuclide after t time,
is initial amount of radioactive nuclide and
is half life of radioactive nuclide
Here
,
and 
So,
so, N = 2.446 mg
mass of uranium-238 decays = (4.60-2.446) mg = 2.15 mg
Answer: last option, what came before the big bang?
Explanation:
The big bang theory states that the universe started as a dense nucleus of matter: a huge amount of matter concentrated in a tiny spot.
This is the conclusion of equations and evidences that prove that the universe has been and continuous to expand: since it has been expanding, there was a moment when it was as small and dense as it is possible.
So, the expansion is the result of violent explosion.
The time during which the expansion has been happening (this is how long ago the big bang occured) has been estimated thanks the the observation of the speed of recesion of the galaxies, but nothing can be told about what came before the bing bang occured.
Answer:
979 atm
Explanation:
To calculate the osmotic pressure, you need to use the following equation:
π = <em>i </em>MRT
In this equation,
-----> π = osmotic pressure (atm)
-----><em> i</em> = van't Hoff's factor (number of dissolved ions)
-----> M = Molarity (M)
-----> R = Ideal Gas constant (0.08206 L*atm/mol*K)
-----> T = temperature (K)
When LiCl dissolves, it dissociates into two ions (Li⁺ and Cl⁻). Therefore, van't Hoff's factor is 2. Before plugging the given values into the equation, you need to convert Celsius to Kelvin.
<em>i </em>= 2 R = 0.08206 L*atm/mol*K
M = 20 M T = 25°C + 273.15 = 298.15 K
π = <em>i </em>MRT
π = (2)(20 M)(0.08206 L*atm/mol*K)(298.15 K)
π = 979 atm