Aluminum foil I think but if not goodluck :)
Answer:
talc mineral and magnetite
Explanation:
<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.
Sun to kelp
kelp to sea urchin
sea urchin to otter
otter to shark
kelp,sea urchin,otter,shark to bacteria
bacteria back to kelp
Answer:
E) 0.90
Explanation:
In TLC (Thin-Layer-Chromatography) retention factor RF is defined as the ratio between distance of the sample and the solvent front. RF is very important in chemistry to know the composition of any sample by comparison.
In the problem, as the sample has a distance of 0,20cm from the solvent front, the distance of the sample is:
2,0cm - 0,20 cm =<em> 1,8 cm</em>. Thus, RF is:
RF = 1,8cm / 2,0cm = 0,90
<em>E) 0,90</em>
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I hope it helps!