Answer:
2.11 billion years.
Explanation:
I hope this helps! Have a great rest of your day!
Answer:
D
Explanation:
Elements in the same group (vertical columns) have the same number of valence electrons. These elements behave similarly because they will either give up or take the same number of electrons to fill their valence shell. Since potassium has 1 valence electron, it will most likely give up one electron. Out of all of the answer options, the only element that is in the same group as potassium is francium.
Answer:
4.64E14
Explanation:
First convert 645 nm to m = 6.4500E-7m. The equation for finding v with these values is the speed of light/wavelength. so 2.998E8/6.4500E-7m.
so your v or frequency would equal 4.64E14
Fun fact you know this is visible light because the visible light range is within the E14 range.
First, it is best to know the chemical formula of pyridine which is C5H5N. To determine the number of carbon atoms present in pyridine, multiply 7.05 mol C5H5N with 5 mol C/ 1 mol C5H5N which then results to 35.35 mol of carbon. Then, multiply the answer to Avogadro's number which is 6.022x10^23 atoms. It is then calculated that the number of carbon atoms in 7.05 moles of pyridine is 2.12x10^25 atoms.
Do you have the picture of the data?