Answer: option C. 2 and 3.
Explanation:
1) Isotopes are atoms of a same element with different number of neutrons. That means that the isotopes of a same element have the same number of protons, since the number of protons is what identify an element.
2) For example, all the atoms of oxygen have 8 protons. But isotope oxygen-16 has 8 neutrons, while oxygen-18 has 10 neutrons.
3) In the figure there are 3 different atoms:
i) atom # 1 has 5 protons and 7 neutrons
ii) atom # 2 has 6 protons and 7 neutrons
iii) atom # 3 has 6 protons and 8 neutrons.
4) Hence the atoms with the same number of protons and different number of neutrons are the #2 and the # 3. So, they are the isotopes of the same element.
<span> rate 3/1= square root of 32/x
square both sides
9/1=32x
x = 32/9
= 3.6
Must be He
molar mass =4
</span>
Hello!
To solve this question, we need to use the
Avogadro's Number, which is a constant first discovered by
Amadeo Avogadro, an Italian scientist. He discovered that in a mole of a substance, there are
6,02*10²³ molecules. Using this relationship, we apply the following conversion factor:

So, 8,50 * 10²⁴ molecules of Na₂SO₃ represent
14,12 moles of Na₂SO₃
Have a nice day!
Answer:
9
Explanation:
The structure of fluorophore used in the experiments has been drawn in the attachment. And from the drawing counting we can say that there are 9 sp2-hybridized carbon atoms present. Fiuorophores are a fluorescent chemical compound that can re-emit light upon light excitation. Normally used to produce absorbance and emission spectra.
Answer:
Explanation:
Burning fossil fuels releases the carbon dioxide stored millions of years ago. ... The concentration of carbon dioxide in the atmosphere has increased more in the northern hemisphere where more fossil fuel burning occurs. Since the Industrial Revolution the concentration globally has increased by about 40 % .