N=6.98*10²⁴
Nₐ=6.022*10²³ mol⁻¹
n(Mg)=N/Nₐ
m(Mg)=n(Mg)M(Mg)=M(Mg)N/Nₐ
m(Mg)=24.3g/mol*6.98*10²⁴/(6.022*10²³mol⁻¹)=281.7 g
Hydrogen is different from alkali metals because it also exhibits the properties of inert gas
Selenium falls in the same column with oxygen therefore it has the same number of valence electrons with oxygen which is 6. It fills the 3d orbital but only 4s and 4p are counted. The electronic configuration is [Ar]3d^10 4s^2.
Answer:
6.9428 kg of CO2
Explanation:
1) Use Avogadro's number that states 1 mole = 6.022 x 10^23 particles. Convert 9.5 x 10^25 molecules into moles.
9.5 x 10^25 CO2 molecules
= 157.75 moles CO2
2) Convert 157.75 moles of CO2 into grams. CO2's molar mass is 44.01g.
= 6942.79g
3) Convert 6942.79 grams into kilograms (divide by 1000):
6.9428 kg