What is the outermost (highest-energy) shell of an element that contains electrons?

How have the greenhouse gasses increased from the year 2000 to 2018

The reactions shown here can be combined to make the overall reaction c(s) + h2o(g) ⇌ co(g) + h2(g) by reversing some and/or dividing all the coefficients by a number. a. c(s) + o2(g) → co2(g) k=1.363×10^69 b. 2 h2(g) + o2(g) → 2 h2o(g) k=1.389×10^80 c. 2co(g) + o2 (g) → 2 co2(g) k=1.477×10^90

Chlorophyll a had the molecular formula c55h72mgn4o5 how many atoms are in this molecule