What is the percent magnesium in a sample made of 24g Mg and 70gCl?

Total percent of magnesium in sample = 25.5%

Explanation:

Given:

Mass of magnesium = 24 gram

Mass of chlorine = 70 gram

Find:

Total percent of magnesium in sample = ?

Computation:

Total mass of sample = Mass of magnesium + Mass of chlorine

Total mass of sample = 24 gram + 70 gram

Total mass of sample = 94 gram

Total percent of magnesium in sample = [Mass of magnesium / Total mass of sample]100

Total percent of magnesium in sample = [24/94]100

Total percent of magnesium in sample = [0.255]100

Total percent of magnesium in sample = 25.5%

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