Answer:
A. 1 = 3 - 2
Explanation:
What defines an expression?
expression - An expression is a sentence with a minimum of two numbers and at least one math operation. This math operation can be addition, subtraction, multiplication, and division.
So if we look at the letter options we can see that A is the best choice.
In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed. The distinction between physical and chemical change is not clear cut.
The answer is liter hope this helped :)
Answer:
The solution is given below
Explanation:
Heat, q= mc∆T
q= 125g x 4.18 J/g∙°C x (21.18x- 24.28) °C
q= -1619.75J
NEGATIVE SIGN INDICATES THAT HEAT IS ABSORBED.
Enthalpy Change, ∆H = 1619.75 7/ 10.5 g
= 154.26 J/g
No. of moles of KBr = Mass of KBr/ Molecular Weight of KBr
=10.5g/119gmol-1
=0.088 mol
∆H= 1619.75 J/ 0.088 mol
= 18.41 kJ/mol
(a) The speed of light in the unknown substance is determined 1.82 x 10⁸ m/s.
(b) The light will bend away from the normal since speed of light in air is not equal to speed of light in the substance.
<h3>What is the speed of light?</h3>
The speed of light passing from air into the substance is calculated as follows;
refractive index = speed of light in air / speed of light in the substance
speed of light in the substance = speed of light in air/refractive index
speed of light in the substance = (3 x 10⁸) / (1.65)
speed of light in the substance = 1.82 x 10⁸ m/s
Thus, the light will bend away from the normal since speed of light in air is not equal to speed of light in the substance.
Learn more about speed of light here: brainly.com/question/104425
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