Answer:
Explanation:
It makes sense because Helium and Hydrogen only hold 1 and 2 subsequent protons/neutrons and electrons. When the Big Bang happened the entire universe was so hot that it was impossible for elements to form since it was impossible for electrons to stay bound to the atoms. After a few seconds the universe began to cool enough for electrons to bond to atoms and create different elements. Since Helium and Hydrogen have 1 and 2 electrons subsequently we can assume that they were the first elements to be created. Also they are the most abundant elements in the Universe which backs up this theory.
Answer:
Explanation:
You can identify an unknown substance by measuring its density and comparing your result to a list of known densities. Density = mass/volume. Assume that you have to identify an unknown metal.
Dude... h2o, thats why ICE FLOATS ON WATER!!!!
Answer : The unit of 
in mol/L.mm Hg is, 
Explanation :
As we know that the is the Henry's Law constant for argon at 
is, 
Now we have to determine the unit of in mol/L.mm Hg
Conversion used for pressure from atm to mmHg is:
1 atm = 760 mmHg
So,
Thus, the unit of in mol/L.mm Hg is,
