Ethylene glycol is known as the main component found in antifreeze.
The molecular formula for ethylene glycol is C₂H₆O₂.
Its molar mass is calculated as C₂H₆O₂ = (2×12) +(6×1) + (216) = 62g/mol
Given that antifreeze comprises 50% by weight, there exists 1 kg of ethylene glycol mixed with 1 kg of water.
ΔTf = Kf×m
ΔTf refers to the change in the freezing point.
= starting temperature of water - freezing temperature of the solution
= 0°C - Tf
= -Tf
Kf stands for the freezing point depression constant of water, which is 1.86°C/m
m is the molarity of the solution.
=(mass/molar mass) where mass of solvent is in kg
=1000g/62 (g/mol) /1kg
=16.13m
Substituting the value into the equation gives us
-Tf = 1.86 × 16.13 = 30
thus Tf = -30°C
The distinction lies in the fact that the candle emits an emission spectrum, while the book reflects an absorption spectrum. In the case of the book, light is observed from all directions, causing its reflection to be diffuse. Explanation: The light emitted by a candle originates from the heat of the flame, composed of a combination of emissions from a black body at that temperature along with emissions from the chemical elements within the candle. On the contrary, the light reflected off a book cover consists of the incident light spectrum minus the wavelengths that trigger electronic transitions in the cover's elements, resulting in dark areas on the spectrum. Consequently, the difference stems from the candle producing an emission spectrum, whereas the book showcases an absorption spectrum. For a book's cover to reflect light specularly, incident rays would need to reflect uniformly, creating dark areas. However, since light is observed from all directions when reflecting off a book, the result is diffuse reflection.
<span>The work done corresponds to the potential energy that the person acquires while ascending the stairs.
work = potential energy acquired = mgh
W = 75kg * 9.8m/s² * 2.50m = 1837.5 J</span>
Response:
(e) thermal expansion
Clarification:
The density, heat of fusion, and melting temperature of a metal are critical factors to consider when increasing its temperature from room temperature to its melting point. These will dictate the following aspects:
Density: refers to the ratio between a body's mass and the space it occupies in the universe.
Heat of fusion: The enthalpy of fusion or heat of fusion signifies the amount of energy required to cause a mole of an element at its melting point to transition from solid to liquid state, under constant pressure.
Melting temperature is defined as the thermal level at which the phase change from solid to liquid takes place under standard atmospheric pressure.
On the other hand, the dilution of metals only influences the volume they will occupy without affecting the heating process
Answer:
Explanation:
Considering that,
The mass of the first vehicle
M1= 328kg
It is traveling in the positive x direction at a speed of
U1 = 19.1m/s
The speed of the second vehicle
U2 = 13m/s, moving in the same direction as the first vehicle..
The mass of the second vehicle
M2 = 790kg
The speed of the second vehicle post-collision
V2 = 15.1 m/s
The speed of the first vehicle following the collision
V1 =?
This represents an elastic collision,
and applying the principle of conservation of momentum
The momentum prior to the collision must equal the momentum afterwards
P(before) = P(after)
M1•U1 + M2•U2 = M1•V1 + M2•V2
328 × 19.1 + 790 × 13 = 328 × V1 + 790 × 15.1
16534.8 = 328•V1 + 11929
328•V1 = 16534.8—11929
328•V1 = 4605.8
V1 = 4605.8/328
V1 = 14.04 m/s
The speed of the first vehicle after the collision is 14.04 m/s
