B. Copper since the rest of the choices are compounds. Copper is an element.
We are given with
136 g P4
excess oxygen
The complete combustion reaction is
P4 + 5O2 => 2P2O5
Converting the amount of P4 to moles
136/123.9 = 1.098 moles
Using stoichiometry
moles P2O5 = 1.098 x 2 = 2.195 moles P2O5
Answer:
2 electrons
E. neon
Explanation:
Metals lose electrons under certain conditions to attain a noble gas electron configuration. Magnesium has 12 electrons and its electron configuration is
1s² 2s² 2p6⁶ 3s²
When magnesium loses 2 electrons, it acquires the electron configuration of neon (10 electrons).
Answer is D, they are compressible