Technically there is only one phase unless you account for a solution where you have a pure liquid with something dissolved in it. Unless you count aqueous as a phase which is just dissolved. Since you are in high school the answer you are looking for is one. <span />
Answer:
The molecular weight is 
Explanation:
From the question we are told that
The mass of the sample is 
The temperature is 
The volume which the gas occupied is 
The pressure is 
Generally from the ideal gas equation we have that
Here n is the number of moles of the gas while the R is the gas constant with value 
=> 
=> 
Generally the molecular weight is mathematically represented as
=> 
=>
Answer:
20 km
Explanation:
he walks 10 km + another 10 km so 20 :)
Nuclear decay or radioactive decay is a process by which the nucleus of an unstable atom loses energy that is in terms of its mass. The radioactivity may cause an atom to lose whichever of its subatomic particles.
The explanation as why some of the atoms go through nuclear decay while others do not its because of the stability of some atoms. Atoms usually tend to follow octet rule, those which do not follow through this may experience the nuclear decay.
Answer:
A)21
Explanation:
To know the difference between the number of electrons in the two atoms, we must first know the number of electrons in the atoms.
For Selenium, Se, we have 34 electrons. The element is in group 6 on the periodic table.
Aluminum on the other hand is in the Boron family with a total of 13 electrons.
The difference,( 34-13) electrons gives a total of 21 electrons
