Answer:
for more details are in the pic
Answer:
C. They don't react with other elements to form compounds
Explanation:
The elements in Group 18 of the periodic table are called "inert", or noble gases.
These elements have their valence shell (the outermost shell of the atom) full of electrons, so they do not gain/give off electrons, and therefore, they do not react with other elements, so they do not form compounds.
In fact, normally the elements try to gain/give off electrons in order to fullfill their outermost shell (the valence shell). For instance, an atom that has 1 electron only in its valence shell, try to "give away" this electron in order to have its outermost shell completed. On the other hand, an atom which has 7 electrons in its valence shell tries to "gain" one electron in order to fullfill the valence shell.
Noble gases, instead, have already 8 electrons in their valence shell, so their valence shell is already completed, therefore they do not react with other elements, and therefore they are called "inert".
Answer:
its letter b
Explanation:
it represents the spectrum of stars
Due to their improved charge transfer and great environmental stability, 2D Dion-Jacobson (DJ) perovskites have recently received a lot of attention.
Unfortunately, due to the scarcity of high-quality single crystals for precise measurements, their fundamental optoelectronic capabilities are mainly unknown. Here, a reactive, low-temperature-gradient crystallization method is created using 1,4-butanediammonium as a short-chain insulating spacer to generate high-quality 2D perovskite single crystal (BDAPbI4). It is discovered that the BDAPbI4 single crystal exhibits a direct bandgap with effective charge collection (μτ = 1.45 × 10−3 cm2 V−1). The BDAPbI4 single crystal in particular exhibits the expected high ion migration activation energy (0.88 eV).
Learn more about charge transfer here-
brainly.com/question/20342415
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Answer:
according to the law of circumference and the perpendicular area of a circle the answer would be c
Explanation: