MOLE CONVERSIONS 1. How many H2O molecules are in 183.2 grams of H20 gas?
2. How much space (L) does 3.614 x 1026 molecules of H2O2 take up?
3. How many molecules are in 3492.5 grams of Mg3(PO4)2?
4. How many grams does 60.2 L of AI(NO3)3 weigh?
5. How many N2 molecules are in 473.2 grams of Nz?
6. How many grams does 80.34 L of H2 weigh?
7. How many grams are in 5.39 x 1025 molecules of Al(OH)3?

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