Answer : The partial pressure of
is, 222.93 torr
Explanation :
Half-life = 2.81 hr = 168.6 min
First we have to calculate the rate constant, we use the formula :



Now we have to calculate the partial pressure of 
The balanced chemical reaction is:

Initial pressure 760 0 0
At eqm. (760-2x) 4x x
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = time passed by the sample = 215 min
a = initial pressure of
= 760 torr
a - x = pressure of
at equilibrium = (760-2x) torr
Now put all the given values in above equation, we get:


The partial pressure of
= x = 222.93 torr
Answer:
color the star with some spacey color(purpel, lavender, white spots)
You can also cover the rest of paper with different objects from space :)
Explanation:
Answer:
The water cycle is driven primarily by the energy from the sun.
Answer:
Radium-226 is a radioactive decay product in the uranium-238 decay series and is the precursor of radon-222. Radium-228 is a radioactive decay product in the thorium-232 decay series. Both isotopes give rise to many additional short-lived radionuclides, resulting in a wide spectrum of alpha, beta and gamma radiations.
Answer:
<em>The correct option is A) The atom has changed over the years.</em>
Explanation:
Option A is not correct because an atom does not change. It remains the same always. The structure of an atom will always contain neutrons, protons and electrons.
Scientific theories tend to change over time as new information is brought up. Novel techniques lead to more advanced experiments and results. As a result, a scientific theory is subjected to change whenever evidence is found for a new theory which challenges the older one.
The atomic theory has changed many times due to novel scientific techniques and experiments.