Making repeated separations of the various substances in the pitchblende, Marie and Pierre used the Curie electrometer to identify the most radioactive fractions. They thus discovered that two fractions, one containing mostly bismuth and the other containing mostly barium, were strongly radioactive.
<h3>What was surprising about pitchblende?</h3>
Since it was no longer appropriate to call them “uranic rays,” Marie proposed a new name: “radioactivity.”
Even more surprising, Marie next found that a uranium ore called pitchblende contained two powerfully radioactive new elements: polonium, which she named for her native Poland, and radium.
<h3>Why is radium more radioactive than uranium?</h3>
It is 2.7 million times more radioactive than the same molar amount of natural uranium (mostly uranium-238), due to its proportionally shorter half-life.
Learn more about highly radioactive elements here:
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brainly.com/question/10257016</h3><h3 /><h3>#SPJ4</h3>
The element which has the electronic configuration is CHLORINE.
The atomic number of chlorine is 17 and it has 7 valence electrons in its outermost shell. Because it needs only one more electrons to have a stable octet, it usually react with metals from group one of the periodic table who are normally willing to donate the single electrons in their outermost shells. The ground state electronic configuration of chlorine atom is 1S^2 2S^2 2P^6 3S^2 3P^5.
He was working with electrons
Answer:
The internal energy is the total amount of kinetic energy and potential energy of all the particles in the system. ... When the substance melts or boils, energy is put in to breaking the bonds that are holding particles together, which increases the potential energy.
Explanation: