The amount of Li present to start the reaction is 55.18g
<u>Explanation:</u>
2Li + Br₂ → 2LiBr
Molecular weight of Br₂ = 159.808 g/mol
Mass of Br₂ present = 225 g
Moles of Br₂ present during the reaction = 225 / 159.808
m = 1.4
Molecular weight of LiBr = 86.845 g/mol
Mass of LiBr formed = 690 g
moles of LiBr produced = 690 / 86.845
m(LiBr) = 7.95
According to the balanced equation, 2 molecules of Li reacts to for 2 molecule of LiBr
So, 7.95 moles of LiBr would require 7.95 moles of Li
The molecular weight of Li is 6.941 g/mol
Thus, the amount of lithium present to start the reaction is
Therefore, the amount of Li present to start the reaction is 55.18g
The force produced on a particle of charge q by an electric field of intensity E is
in our problem, the force is F=5.0 N while the charge is q=2.0 C, so we can find the intensity of the electric field:
The relationship between electric field intensity and potential difference
between two points A and B is
where d is the distance between the two points. By using d=6.0 m, we find
where the negative sign means that the initial point, VA, is at higher potential than the final point VB.
Answer:
<em>A) it transforms a small force acting over a large distance into a large force acting over a small distance.</em>
Explanation:
The hydraulic lever works based on Pascal's law of transmission of pressure through a fluid. In the hydraulic lever, the pressure transmitted is the same.
Pressure transmitted P = F/A
where F is the force applied
and A is the area over which the force is applied.
This pressure can be manipulated on the input end as a small force applied over a small area, and then be transmitted to the output end as a large force over a large area.
F/A = f/a
where the left side of the equation is for the output, and the right side is for the input.
The volume of the displaced fluid will be the same on both ends of the hydraulic lever. Since we know that
volume V = (area A) x (distance d)
this means that the the piston on the input smaller area of the hydraulic lever will travel a greater distance, while the piston on the larger output area of the lever will travel a small distance.
From all these, we can see that the advantage of a hydraulic lever is that it transforms a small force acting over a large distance into a large force acting over a small distance.
Speed is a derivation of energy (thats what my science teacher said)
<span>Water will diffuse down gradients of water potential, just as heat will flow down gradients of temperature and rocks will roll down gradients of gravitational potential</span>