Helium - 4 isotope has 2 protons and 2 neutrons.
Its atomic number is 2 (the number of protons). Atomic number is the number of protons in the atom of an element and it identifies the element. All the isotopes of an element have the same atomic number (same number of protons). So, all the isotopes of hellium have 2 protons.
The number 4 that identifies the helium - 4 isotope is the mass number, i.e. the number of protons plus the number of neutron. So, helium-4 isotope has 2 protons and 2 neutrons. While, other isotopes of helium have 2 protons but different number of neutrons.
The atomic number enable us to deduce the number of electrons in an atom because the atoms are neutral, which implies that the positive and negative charge are equal. Given that the magnitude of the charge of electons and protons are equal but the sign is opposed (protons are positve and electrons are negative) the number of electrons in the atom equals the number of protonts. That is why the atomic number is also the number of electrons of the atom.
Answer:
i believe it is 17x=(4)x*4 +11*(0)
Explanation:
Well one mole of stuff, any stuff, including carbon dioxide, specifies
6.022
×
10
23
individual items of that stuff.
Explanation:
And thus we work out the quotient:
7.2
×
10
25
⋅
carbon dioxide molecules
6.022
×
10
23
⋅
carbon dioxide molecules
⋅
m
o
l
−
1
≅
120
⋅
m
o
l
carbon dioxide
.
This is dimensionally consistent, because we get an answer with units
1
m
o
l
−
1
=
1
1
mol
=
m
o
l
as required.
Answer:
hydrate
Explanation:
when a hydrate is heated,it changes color due to the exothermic reaction taking place.the structure of the complex changes but not entirely.this result in the sample to to not dissolve completely and we can observe the small traces of the sample.