Answer:
It does not contain free mobile ions
Explanation:
Solid sodium chloride does not conduct electricity because it does not contain free mobile ions.
- Although sodium chloride is an ionic compound, in solid state, there is absence of free mobile ions.
- In aqueous solutions or in molten form, ionic compounds can conduct an electric current using free mobile ions as carriers.
- Therefore, they are electrolytes.
In solid state ions are arranged into crystal lattice and will not conduct a current of electricity.
Answer:
electrons fill lower energy levels first before occupying higher energy levels.
Explanation:
The Aufbau's principle describes that electrons fill lower energy levels first before occupying higher energy levels.
In writing the electronic configuration of atoms, the Aufbau's principle is one of the most important principles to consider.
It states that "sublevels with with lower energies are filled up before those with higher energies".
Sublevels do not fill up in numerical order.
Number of atoms : 1.26 x 10²³
<h3>Further explanation </h3>
The mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
0.21 moles of Al, so n = 0.21
Number of atoms :

It would be 1 or 2 because if the number is higher than 5 you need to round up , if its lower than 5 you need to round down.
Only coniferous trees have thin, waxy, needle-like leaves that drop throughout the year and help to retain water.
<h3>What are coniferous trees?</h3>
Coniferous trees are evergreen trees that produce cones.
In addition, they produce waxy and needle-like leaves that help them conserve water by limiting the evapotranspiration rate as a result of reduced surface area.
Examples of conifers include pine trees and spruces.
More on conifers can be found here: brainly.com/question/23222416