Everyday Science MCQs

5120 MCQs  (Page 460 of 512)

Atomic number of Mn is 25 what is the electronic configuration in the ground state________________?
A. 1s2 2s2 2p6 3s2 3p6 3d7
B. 1s2 2s2 2p6 3s2 3p6 4s2 4p5
C. 1s2 2s2 2p6 3s2 3p5 3d10
D. 1s2 2s2 2p6 3s2 3p6 4s23d5
What is the main composition of the sun?
A. Oxygen and ammonia
B. Hydrogen and helium
C. Hydrogen and oxygen
D. Methane and hydrogen