Question

Chlorophyll a is one of the green pigments found in plants. Chlorophyll a has the molecular formula C55H72MgN4O5. How many atoms are in this molecule?

136
137
138

Answer 1

The subscript represents how much of that atom there are

\(C_{55}\) => 55 Carbon atoms

So,
\(C_{55}H_{72}MgN_{4}O_{5}\)

Is this the formula given?

Answer 2

55 + 72 + 4 + 5

Answer 3

or that

Answer 4

almost
in chemistry when there is no subscript, it is assumed that there is 1 atom
for example, H2O, the O doesn't have a subscript but we know there's an oxygen atom there

therefore
C55H72MgN4O5 --> 55 + 72 + 1 + 4 + 5