The correct option is B.
Mendeleev was the one who originated the idea of arranging elements in the periodic table according to their chemical and physical properties. He left spaces in the periodic table and predicted the discovery of those elements that had not been discovered then. One of these elements is Gallium. He predicted that gallium is going to be a metal and he gave the properties that the element will possess. He also predicted that the element gallium will be placed under aluminium in the periodic table.
Answer:
A - Liquid molecules forming a gas and gas molecules forming a
liquid are equal in number.
Explanation:
A P E X
It take more energy to break the bonds of the reactants and less energy is given off when the product bonds are formed.
<h3>What is Energy?</h3>
Energy is defined as the ability to do work. Work is done in the breaking or formation of bonds.
The standard Enthalpy (ΔH) of water which was formed in the given reaction is negative.
ΔH= Δproduct - Δreactant
This means that the energy to break the bonds of the reactants is more.
Read more about Enthalpy here brainly.com/question/14291557
Answer:
in a chemical reaction of NaOH with H2O, after NaOH is completely disassociated, we will find Na+ and OH- ions in the solution. (option C).
Explanation:
In a reaction where NaOH is added to H2O.
NaOH is considered a strong base, this means that in an aqueous solution ( in water) it's able to completely disassociate in ions.
There will not remain any NaOH in the solution. This means option D is not correct.
The ions in which NaOH will disassociate are : NaOH → Na+ + OH-
These ions we will find in the solution.
Not only Na+ because NaOH is a strong base, so there will be a lot of OH- ions as well in solution.
This means in a chemical reaction of NaOH with H2O, after NaOH is completely disassociated, we will find Na+ and OH- ions in the solution.