Answer:
Hello your question is poorly written below is the well written question
Uranium, an important component of both nuclear weapons and nuclear reactors, has two major isotopes, U-238, which has a half-life of approximately 4.5 billion years, and U-235, which has a half-life of approximately 700 million years. Both were present in equal amounts at the time of the creation of the Earth, 4.5 billion years ago. How many years after the creation of the Earth had the amount of radiation from uranium decayed to half the amount present at the time of the creation of the Earth
Answer : 140 billion years
Explanation:
Given that :
U-238 h1/2 = 4.5 billion years
U-235 h1/2 = 700 million years
At the beginning both Isotopes where present in equal amount
Determine the T years before the amount of Uranium decays to Half
T = ? N'2 = N1 / 2
we know that N = No ( 1/2 )^h where h = time / half-life time
attached below is the detailed solution of the given problem
Answer: 11.5 grams
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution
where,
Morality = 0.612 M
n= moles of solute
= volume of solution in ml = 100 ml
Now put all the given values in the formula of molarity, we get

Therefore, the mass of copper (II)nitrate required is 11.5 grams
Answer:
Incomplete
Explanation:
I wouldn't say that a scientific theory is wrong.
It is the best we have at the time, based on all available knowledge .
As each new discovery is made, scientists modify the theory to fit the new knowledge.
The scientific method is a never-ending process.
Answer:

Explanation:
Hello there!
In this case, by bearing to to mind the given conditions, it is firstly possible to determine the initial volume of the closed system via the ideal gas equation:

Which is V1 in the Charles' law:

And of course, T1 is 298.15 (25+273.15). Therefore, by solving for V2 as the final volume, we obtain:

Best regards!
Hey there ! :
<span>2 Na + 2 H2O = 2 NaOH + 1 H<span>2
</span></span>Sodium<span> + </span>Dihydrogen Monoxide<span> = </span><span>Natriumhydroxid</span><span> + </span>Hydrogen
Coefficients:
Reagents : Na = 2
H2O = 2
Products : NaOH = 2
H2 = 1