Answer : option B) Gravity acting on the edges of plates and friction between the plate and the asthenosphere.
Explanation : The gravitational force acting on the edges of the tectonic plates raise a friction between the plate and the asthenosphere, which results into the motion of the tectonic plates.
Usually, the tectonic plates are found to move because of the intense heat produced from the Earth's core which causes the molten rock in the mantle layer to move and make a motion. It moves in a pattern which is called as convection cell that forms when the warm material rises, and cools, later eventually sink down producing the motion in the tectonic plates.
Answer:
alkali metal
Explanation:
The alkali metals in period 4 will have the lowest ionization energy of the elements in the period.
Across a period ionization energy increases progressively from left to right due to decreasing atomic radii caused by the increasing nuclear charge which is not compensated for by successive electronic shells.
- Ionization energy is the energy needed to remove the most loosely bound electrons of an atom in the gas phase in the ground state.
- The measure of the readiness of an atom to lose an electron is the ionization energy.
Down a group, it decreases.
Answer: ![Ne:1s^22s^22p^6](https://tex.z-dn.net/?f=Ne%3A1s%5E22s%5E22p%5E6)
![Li:1s^22s^1](https://tex.z-dn.net/?f=Li%3A1s%5E22s%5E1)
![N:1s^22s^22p^3](https://tex.z-dn.net/?f=N%3A1s%5E22s%5E22p%5E3)
![S:1s^22s^22p^63s^23p^4](https://tex.z-dn.net/?f=S%3A1s%5E22s%5E22p%5E63s%5E23p%5E4)
![Sc:1s^22s^22p^63s^23p^64s^23d^1](https://tex.z-dn.net/?f=Sc%3A1s%5E22s%5E22p%5E63s%5E23p%5E64s%5E23d%5E1)
Explanation:
Electronic configuration represents the total number of electrons that a neutral element contains. We add all the superscripts to know the number of electrons in an atom. The electrons are filled according to Afbau's rule in order of increasing energies.
The electronic configuration for given elements is as follows:
![Ne:10:1s^22s^22p^6](https://tex.z-dn.net/?f=Ne%3A10%3A1s%5E22s%5E22p%5E6)
![Li:3:1s^22s^1](https://tex.z-dn.net/?f=Li%3A3%3A1s%5E22s%5E1)
![N:7:1s^22s^22p^3](https://tex.z-dn.net/?f=N%3A7%3A1s%5E22s%5E22p%5E3)
![S:16:1s^22s^22p^63s^23p^4](https://tex.z-dn.net/?f=S%3A16%3A1s%5E22s%5E22p%5E63s%5E23p%5E4)
![Sc:21:1s^22s^22p^63s^23p^64s^23d^1](https://tex.z-dn.net/?f=Sc%3A21%3A1s%5E22s%5E22p%5E63s%5E23p%5E64s%5E23d%5E1)
According to the Bronsted-Lowry definitions, an acid is any substance that donates hydrogen ions; whereas, a base is any substance that accepts hydrogen ions.
In the first reaction, water is acting as an acid because it donates a hydrogen ions.
In the second reaction, water is acting as a base because it accepts a hydrogen ion.
In the third reaction, water is again donating a hydrogen ion so it is the acid.
In the fourth reaction, water is acting as a base by accepting the hydrogen ion from the ammonium ion.
Answer:
potassium (K) and bromine (Br)
Explanation:
- Periodic table is a table of elements in terms of rows and columns in terms of their chemical and physical properties.
- Elements in the same group or columns have similar physical and chemical properties. For example, elements in the same group have the same number of valence electrons or valency.
- Elements in the same period or rows have similar number of energy levels. For example, potassium and bromine belong to the same period in the periodic table and thus have the same number of energy levels.