Answer:
It should be *+3
Explanation:
Al3+ indicates an ion of aluminum having a charge of + 3. I.e., since an aluminum atom normally has 13 protons and 13 electrons, this ion has 10 electrons (-10 charge) and 13 protons (+ 13 charge) giving it a charge of + 3 (-10 + 13 = +3).
The other i.d.i.ot answered unhelpfully
Answer:
The statement which best explains the difference between the light waves travelling through a vaccuum and light waves travelling through a medium is -"<u>When light waves travel through a vacuum, they travel faster than when they travel through a medium."</u>
Explanation:
Light waves are faster in vacuum because The refractive index of vacuum is the lowest since there is no barrier in the way of light propagation in vacuum. Demonstrate that the maximum speed of light in vacuum.
In a vacuum, light flies at 186,283 mph. Light flies at 186,200 mph in the air, or 56 mph slower. In another medium, such as water, light travels at 139,712 mph, or around 3/4 of the speed of light in a vacuum.
<u>LIGHT WAVES -: </u> Light waves are a form of electromagnetic wave that includes both visible and invisible to the naked eye wavelengths on the electromagnetic spectrum. The average human eye can see light with wavelengths ranging from 390 to 700 nanometers, or nm.
Forms of light waves comprises of Radio waves , microwaves , infrared waves , visible light etc.
The correct answer is
C. Light can pass through Object B faster than it can pass through Object A.
In fact, the index of refraction of a material is defined as:

where c is the speed of light in vacuum and v is the speed of light in the material. Rearranging the equation, we can write the speed of light in the material as:

So we that, the smaller the refractive index n, the greater the speed of light in the material, v. In this problem, object B has lower refractive index than object A, so light travels faster in object B.
Answer:
3.87 or 3.9 mg
Explanation:
2.7h * 60mins = 162mins
number of 1/2 lives = 162/22= 7.364
amount remaining = 639(1/2)^7.364 = 3.8796
answer = 3.87 or 3.9