Answer:
Francium (Fr)
Explanation:
From the given choices, francium will have the lowest ionization energy.
Ionization energy is the energy required to remove the most loosely held electron within an atom.
The magnitude of the ionization energy depends on the characteristics of the atom in relation to its nuclear charge, atomic radius, stability etc.
- Generally on the periodic table, ionization energy increases from left to right on the table
- As you go from metals to non-metals and to gases, the value of the ionization energy increases steadily.
- Down the group, the value reduces.
- Since Francium is the most metallic of all the given choices, it has the highest ionization energy.
Answer:
Ash and dust fill the air and reduce sunlight.
Explanation:
Ash and dust comes out of volcanoes, and it is bad for the environment. Polluting the air and causing fogginess, it also reduces sunlight.
What are some of the body's internal defenses. The skin helps protect stuff to!
Answer:
trigonal pyramidal
Explanation:
In NF3, the nitrogen atom is sp3 hybridized. Now we must remember that according to the VSEPR theory, the number of electron pairs in the valence shell of the central atom in a molecule determines its shape.
Here, the nitrogen atom is the central atom and its outermost shell is surrounded by four electron pairs - one lone pair and three bond pairs. This means that it has a tetrahedral electron pair geometry.
However, due to the lone pair, the three fluorine atoms are arranged in a trigonal pyramidal geometry. Hence the correct shape of the molecule is trigonal pyramidal.