Answer:
Temporary in nature.
No new substance is formed.
Explanation:
Temporary in nature: Does not affect the internal structure of a substance, only the molecules are rearranged.
No new substance is formed: Most of the physical changes are reversible. We can obtain the substance back even after the change.
hope this helps
have an awesome day -TJ
<u>Answer:</u> The percentage abundance of
and
isotopes are 77.5% and 22.5% respectively.
<u>Explanation:</u>
Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.
Formula used to calculate average atomic mass follows:
.....(1)
Let the fractional abundance of
isotope be 'x'. So, fractional abundance of
isotope will be '1 - x'
- <u>For
isotope:</u>
Mass of
isotope = 35 amu
Fractional abundance of
isotope = x
- <u>For
isotope:</u>
Mass of
isotope = 37 amu
Fractional abundance of
isotope = 1 - x
Average atomic mass of chlorine = 35.45 amu
Putting values in equation 1, we get:
![35.45=[(35\times x)+(37\times (1-x))]\\\\x=0.775](https://tex.z-dn.net/?f=35.45%3D%5B%2835%5Ctimes%20x%29%2B%2837%5Ctimes%20%281-x%29%29%5D%5C%5C%5C%5Cx%3D0.775)
Percentage abundance of
isotope = 
Percentage abundance of
isotope = 
Hence, the percentage abundance of
and
isotopes are 77.5% and 22.5% respectively.
Answer:
Chromosphere
Explanation:
You see the middle layer of the sun’s atmosphere, the Chromosphere, at the start and end of a total eclipse.
Answer:
108.6 g
Explanation:
- 2NaN₃(s) → 2Na(s) + 3N₂(g)
First we use the <em>PV=nRT formula</em> to <u>calculate the number of nitrogen moles</u>:
- R = 0.082 atm·L·mol⁻¹·K⁻¹
- T = 0 °C ⇒ 0 + 273.2 = 273.2 K
<u>Inputting the data</u>:
- 1.00 atm * 56.0 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 273.2 K
Then we <u>convert 2.5 moles of N₂ into moles of NaN₃</u>, using the <em>stoichiometric coefficients of the balanced reaction</em>:
- 2.5 mol N₂ *
= 1.67 mol NaN₃
Finally we <u>convert 1.67 moles of NaN₃ into grams</u>, using its <em>molar mass</em>:
- 1.67 mol * 65 g/mol = 108.6 g