Calculate the number of co2 molecules ( nco2) in 0.0693 mol of co2

0.42×10²³ molecules of CO₂.

Explanation:

Given data:

Number of moles of CO₂ = 0.0693 mol

Number of molecules of CO₂ = ?

Solution:

The given problem can be solve by using the Avogadro number.

Avogadro number is the number of atoms , ions and molecules in one gram atom of element, one gram molecule of compound and one gram ion of substance.

The number 6.022×1023 is called Avogadro number.

1 mole of CO₂ contain 6.02 ×10²³ molecules of CO₂

0.0693 moles of CO₂ contain = 0.42×10²³ molecules of CO₂

0.0693× 6.02 ×10²³ = 0.42×10²³

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