Answer:
Element X with atomic number 10 and atomic mass 21
Element Z with atomic number 10 and atomic mass 22
Explanation:
Isotopy is the existence of two or more atoms of the same element having the same atomic number but different mass numbers due to the differences in the number of neutrons in their various nuclei.
- Isotopes of an element have the same electronic configuration.
- They share the same chemical properties
- They only differ in their masses.
So, Element X and Z with atomic number 10 which is their number of electrons are isotopes. Their mass number, 21 and 22 differs.
<span>Since,
1000 grams of water = 1000 mL of water</span><span>
So,
At any of the given temperature:
</span>1000 mL = 10 x 100 mL
<span>
moles of NH4Cl = 53.5/53.49
= 1.0 m
= 1.0 mol/Kg
Delta T = 2 x 1.86 x 1.0
= 3.72 c
= - 3.72 °C</span>
<span>There are 2 carbon atoms in ethanoic acid. Other name of such substance is acetic acid. It is a colorless liquid carboxylic acid with the chemical formula CH3COOH. It has antibacterial and antifungal properties.</span>
LiF or lithium fluoride is the non covalent molecule or ionic compound.
Option 3.
<h3><u>Explanation:</u></h3>
Covalent molecules are those molecules which do have actual bonds between the atoms present in the molecule by sharing of the electrons. But in ionic molecules, there's no actual bonds between the atoms, but the oppositely charged ions are attracted towards each other by means of electrostatic force of attraction.
The molecules that are formed by the atoms with high electronegativity and electropositivity are actually ionic because the atoms with high electronegativity are able to actually gain electron readily and the atoms with high electropositivity are actually ready to give the electrons to the electronegative elements.
Lithium is highly electropositive and fluoride is highly electronegative. So they establish an ionic bond. But other molecules like fluorine molecule has both the electronegative elements, Carbon monoxide has carbon which isn't electropositive highly, and ammonia has hydrogen which isn't electropositive.
So lithium fluoride is the ionic compound.
Some material from meteors lingers in the mesosphere, causing this layer to have a relatively high concentration of iron and other metal atoms. Very strange, high altitude clouds called "noctilucent clouds" or "polar mesospheric clouds" sometime form in the mesosphere near the poles.
I really hope this helps! I wish you the best of luck!