Red phosphorus reacts with liquid bromine in an exothermic reaction: 2 P(s) + 3 Br₂(l) ► 2PBr₃(g)
ΔH° = -243.0 kJ
Calculate the enthalpy change when 2.63 g of red phosphorus reacts with 25.0 g of Br₂.

8

explanation:

each principal energy level above the first contains one s orbital and three p orbitals. a set of three p orbitals, called the p sublevel, can hold a maximum of six electrons. therefore, the second level can contain a maximum of eight electrons - that is, two in the s orbital and 6 in the three p orbitals.

mark brainliest and have a great day!

i would say b

explanation:

but i think i would need more information than that

it would be d. henry moseley

hope this !

and sorry if i'm late. have a good rest of your day! : d

there are two significant figures.