How many times stronger was the earth's magnetic field in 800 b. c.? a. 1.5 times b. 2 times c. 3 times d. 4 times

b. 2 times

Explanation:

The earth´s magnetic field decays approximately 10% every 150 years, so form that we can extrapole the fact that 2800 years ago it would be approximately 2 times stronger the earths magnetic field compared to the earth´s magnetic field at this time.

why do the isotopes of a particular element behave differently in nuclear reactions but the same in chemical reactions? chemical reactions involve changes to electrons in an atom; isotopes do not differ in electrons, and so they react the same way during chemical changes.

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.