Answer:
Precipitation is the formation of a solid from a solution. It is necessary to centrifuge the precipitate to exert sufficient forces of gravity to bring the solid particles in the solution to come together and settle
Explanation:
When you centrifuge precipitate it enables the nucleation to form.
Centrifuging the precipitate helps in determining whether a certain element is present in a solution or not.
In a solution, a SOLUTE is the substance being dissolved.
In a solution, a SOLVENT is the substance in which something is dissolved.
For example in salt water, the salt is the solute. And the water is the solvent. Usually, which substance has a larger amount in the solution can be called a solvent. It doesn't matter if it's a gas, solid, or liquid. They can all be solute or solvents.
Answer : The temperature of the hot reservoir (in Kelvins) is 1128.18 K
Explanation :
Efficiency of carnot heat engine : It is the ratio of work done by the system to the system to the amount of heat transferred to the system at the higher temperature.
Formula used for efficiency of the heat engine.

where,
= efficiency = 0.780
= Temperature of hot reservoir = ?
= Temperature of cold reservoir = 
Now put all the given values in the above expression, we get:



Therefore, the temperature of the hot reservoir (in Kelvins) is 1128.18 K
Answer:

Explanation:
The incident angle is
so the reflected ray will also be
.
The normal divides the angle between the incident and reflected ray. So, the angle between them would be

So, the angle between the incident and reflected rays is
.
Answer:
Torque = 1191.68 N-m
Explanation:
Given data
mass m = 76 kg
standingdistance r = 1.6 m
Solution
we get here torque that si express as
torque = force × distance ................1
torque = r × F sin(theta)
and we know that
F = mg .........2
and g = 9.8 m/s²
put here value in equation 1 we get
Torque = 76 × 1.6 × 9.8 × sin(90)
Torque = 1191.68 N-m