Answer:
C
Explanation:
The kinetic energy of a body is the energy due to the motion of a body. It is mathematically given as;
Kinetic energy = 
m v²
m is the mass of the body
v is the velocity
Now, let us find the K.E from the given choices;
Option C will have the greatest kinetic energy;
mass = 0.14kg , v = 40m/s
Kinetic energy = x 0.14 x 40² = 112J
Answer:
10%
Explanation:
Given data:
Actual yield = 0.13 moles
Percent yield = ?
Solution:
Balanced chemical equation.
3H₂ + N₂ → 2NH₃
First of all we will calculate the mass of given moles of ammonia.
Number of moles = mass / molar mass
Mass = 0.13 × 17 g/mol
Mass = 2.21 g
2.21 g is experimental yield of ammonia.
Hydrogen is limiting reactant because only two moles of hydrogen present.
we will compare the moles of hydrogen and ammonia from balance chemical equation.
H₂ : NH₃
3 : 2
2 : 2/3×2 = 1.33 moles
Mass of ammonia
Mass = number of moles × molar mass
Mass = 1.33 mol × 17 g/mol
Mass = 22.61 g
Percent yield:
Percent yield = actual yield / theoretical yield × 100
Percent yield = 2.21 g / 22.61 g
Percent yield =9.8% which is almost 10%
The empirical formula : CH₃
<h3>Further explanation</h3>
Given
2.5 g sample
2.002 g Carbon
Required
The empirical formula
Solution
Mass of Hydrogen :
= 2.5 - 2.002
= 0.498
Mol ratio C : H :
C : 2.002/12 = 0.167
H : 0.498/1 = 0.498
Divide by 0.167 :
C : H = 1 : 3
