Consider the reaction. 2Pb(s)+O2(g)⟶2PbO(s)

An excess of oxygen reacts with 451.4 g of lead, forming 317.3 g of lead(II) oxide. Calculate the percent yield of the reaction.

percent yield:

The percent yield of reaction = 65.27%

Reaction

2Pb(s)+O₂(g)⟶2PbO(s)

mass of Lead(Pb) = 451.4 g

mol of Pb (MW=207 g/mol) :

mol of lead(II) oxide (PbO) based on mol Pb as a limiting reactant(Oxygen as an excess reactant) :

mass of PbO(MW=223 g/mol)⇒theoretical :

The percent yield :

theoretical = 486.14 g

actual = 317.3 g

first let us lay out the formula for potential

and kinetic energy:

pe = mgh

ke = (mv^2)/2

where: m=mass, v=velocity, g=gravitational

acceleration, h=height

calculating for mass using the known values of

pe:

340j = m (9.81 m/s^2) (50ft) (1m/3.28ft)

m = 2.27 kg

the law of conservation of energy states that

energy is neither created nor destroyed. therefore, the change in kinetic

energy from 50 ft to 35 ft would be equal to the change in potential energy

from 50 ft to 35 ft. however it would be opposite in signs since one is losing

while other is gaining.

ke(35ft) – ke(50ft) = - [ pe(35ft) – pe(50ft]

ke(50ft) = 0 since the brick is initially at rest

ke(35ft) = 340j - 2.27kg (9.81 m/s^2) (35ft)

(1m/3.28 ft)

ke(35ft)

= 102.38 j

its first and third is your answer i did the qustion the fourth isnt right