Crude oil may contain hundreds of different types of hydrocarbons. some examples include: butane (c₄h₁₀)
dodecane (c₁₂h₂₆)
octane (c₈h₁₈)
benzene (c₆h₆) many common fuels, such as gasoline and kerosene, are combinations of these substances or others. when these fuels burn, they combine with oxygen (o₂) to produce carbon dioxide (co₂) and water (h₂o). identify each of the highlighted materials as an element, a compound, or a mixture, and explain your reasoning.

The answer to your question is:

Explanation:

Butane (C₄H₁₀)                   Compound      It's composed by C and H

Dodecane (C₁₂H₂₆)            Compond        It's composed by C and H

Octane (C₈H₁₈)                   Compound      It's composed by C and H

Benzene (C₆H₆)                Compound      It's composed by C and H

Oxygen (O₂)                     Element           It's only oxygen

Carbon dioxide (CO₂)      Compound      It's composed by C and O

Water (H₂O)                      Compound      It's composed by H and O

Gasoline                           Mixture             It's composed by many hydrocarbons

Kerosene                          Mixture            It's a mixture of hydrocarbons

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