Due to the lack of information provided, the best I can give you is this:
In Chemistry, the letter c most commonly refers to specific heat, which is present in the ratio J/g°C.
Hope it helps :)
Answer:
Number of neutrons and stability
Explanation:
An isotope of an element is basically the same element but with different number of neutrons. For example here, boron can exist in the forms of boron-10 and boron-11, and so the latter would have one more neutron than the former one.
Adding an extra neutron may or may not disrupt the strong force that much, and so the half-life and stability of the new isotope can be slightly different than its most stable one.
Answer:
CH4 +O2 => CO2 + 2 H2O
None were in excess
Explanation:
Equation for the reaction is,
CH4 + O2 =>CO2 +2 H2O
No of moles of CH4 = (20 /1000)/24 =0.02 /24 = 0.00083
No of moles of O2 =20 /24000 = 0.0083
CH4 : O2 = 1:1
THEREFORE
None of the gases were in excess.
<u>Answer:</u> The fraction of atom's mass contributed by nucleus is 0.99
<u>Explanation:</u>
Nucleons are defined as the sub-atomic particles which are present in the nucleus of an atom. Nucleons are protons and neutrons.
The isotopic symbol of Helium-4 atom is 
Number of electrons = 2
Number of protons = 2
Number of neutrons = 4 - 2 = 2
We are given:
Mass of He-4 atom = 
Mass of 1 electron = 
Calculating the mass contributed by the nucleus = 
Mass of the nucleus of He-4 atom = 
To calculate the fraction of atom's mass contributed by the nucleus, we use the equation:

Putting values in above equation, we get:

Hence, the fraction of atom's mass contributed by nucleus is 0.99
You did not specify the types, but I believe the answer would be gamma radiation.