Which sequence of coefficients will balance the following equation? Mg (s) + O2 (g) --> 2MgO (s) A. 4,1,2
B. 1,1,2
C. 2,1,2
D. 3,1,2

Read the given expression. x = number of protons − number of core electrons which of the following explains the identity of x and its trends across a period? x is the effective nuclear charge, and it remains constant across a period. x is the screening constant, and it remains constant across a period. x is the effective nuclear charge, and it increases across a period. x is the screening constant, and it increases across a period.

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )

What are the 4 phases of matter in order of increasing engery content?