1. In an energy pyramid, which way does energy transfer? A. From the top of the pyramid to the bottom
B. From the bottom of the pyramid to the top
C. Between the top Ind the bottom
D. Energy doesn't transfer between layers

It is B, From the bottom of the pyramid to the top

The total pressure after one half is 6.375 atm.

Explanation:

The initial pressure of product is increases while the pressure of reactant would decrease.

Balanced chemical equation:

2N₂O  → 2N₂ + O₂

The pressure of N₂O is 5.10 atm. The change in pressure would be,

N₂O = -2x

N₂ = +2x

O₂ = +x

The total pressure will be

P(total) = P(N₂O) + P(N₂)  + P(O₂)

P(total) = ( 5.10 - 2x) + (2x)  + (x)

P(total) = 5.10 + x

After one half life:

P(N₂O)  = 1/2(5.10) = 5.10 - 2x

x = 5.10 - 1/2(5.10) /2

x = 5.10 - 0.5 (5.10) /2

x = 5.10 - 2.55 / 2

x = 2.55 /2 = 1.275 atm

Thus the total pressure will be,

P(total) = 5.10 + x

P(total) = 5.10 + 1.275

P(total) = 6.375 atm