Answer:
A
Explanation:
Remember the number of valence electrons represent the group number. As shown in figure, there is only one electron in the valence shell. Therefore, this element belongs to group 1 elements also called as Alkali metals.
Furthermore, the number of electrons in a neutral atom equals number of protons. Hence, there are 11 protons in this element.
Also, number of protons equal atomic number therefore, the atomic number of this element is 11. And, by checking periodic table, the element having atomic number 11 is Sodium (Na).
Ionization energy, also called ionization potential, in chemistry, the amount of energy required to remove an electron from an isolated atom or molecule
178 of each species
178 protons
178 neutrons
And 178 electrons
There are 1.923×10^23 formula units in 30.4g mgcl2
molar mass of mgcl2= 95.211g/mol
magnesium= 24.305g/mol
chlorine= 35.45g/mol times 2
24.305+(35.45*2)= 95.211g/mol
sample divided by molar mass times Avogadro's number gives u the formula units
30.4÷ 95.211= .31929
.3193*6.022=1.9288
