Answer:
Chemical Change
Explanation:
It changes color and produces vapor when the foil is added to the solution.
<u>Answer:</u>
<u>For a:</u> The wavelength of light is 
<u>For b:</u> The light is getting absorbed
<u>Explanation:</u>
To calculate the wavelength of light, we use Rydberg's Equation:

Where,
= Wavelength of radiation
= Rydberg's Constant = 
= Higher energy level = 7
= Lower energy level = 3
Putting the values in above equation, we get:

Hence, the wavelength of light is 
There are two ways in which electrons can transition between energy levels:
- <u>Absorption spectra:</u> This type of spectra is seen when an electron jumps from lower energy level to higher energy level. In this process, energy is absorbed.
- <u>Emission spectra:</u> This type of spectra is seen when an electron jumps from higher energy level to lower energy level. In this process, energy is released in the form of photons.
As, the electron jumps from lower energy level to higher energy level. The wavelength is getting absorbed.
There’s only one measurement the question doesn’t make sense
Answer:
Approximately
.
Explanation:
Note that both figures in the question come with four significant figures. Therefore, the answer should also be rounded to four significant figures. Intermediate results should have more significant figures than that.
<h3>Formula mass of strontium hydroxide</h3>
Look up the relative atomic mass of
,
, and
on a modern periodic table. Keep at least four significant figures in each of these atomic mass data.
Calculate the formula mass of
:
.
<h3>Number of moles of strontium hydroxide in the solution</h3>
means that each mole of
formula units have a mass of
.
The question states that there are
of
in this solution.
How many moles of
formula units would that be?
.
<h3>Molarity of this strontium hydroxide solution</h3>
There are
of
formula units in this
solution. Convert the unit of volume to liter:
.
The molarity of a solution measures its molar concentration. For this solution:
.
(Rounded to four significant figures.)
Answer:
True
Explanation:
Natural gas. Natural is its name. (I think)