Answer:
A
Explanation:
The group number of an element is equal to the number of electrons the outermost shell (or highest energy level) contains
The products of the neutralization reaction between hydrochloric acid and magnesium hydroxide are Magnesium chloride and water.
Your question, I guess, How do vapour and gases differ...
Answer:
1.) Vapour is the changed state of any liquid either due to boiling or evaporation
2.) Vapour are more energetic as they have absorbed the latent heat of vaporization whereas Gases are low in energy because they are already in gaseous form at room temperature.
3.) Vapour have boiling points above room temperature while gases have their boiling point below room temperature.
It’s A because +1500 kJ is before the arrow. it’s in the reactant side. so it is endothermic.
Answer:
The correct option is the second option
Explanation:
Generally, the aim of science is to understand a particular concept in the best and the most correct way possible; hence experiments are done and repeated to ensure an explanation is actually true about a concept or need modification.
The atomic models have also been a "beneficiary" of this process. The different atomic models are usually been improved upon as scientists leaned more. For example, the Dalton's atomic theory has been modified to a more correct atomic description; some of which are shown below
(1) Dalton's theory suggested that an atom is the smallest unit of a molecule. We know now from different experiments (by J. J Thompson and Rutherford) that atoms are not the smallest molecules and are made up of smaller particles known as protons, neutrons and electrons.
(2) Dalton's theory suggested that atoms of the same elements are alike in all aspects. The knowledge of isotopy shows this is not always the case. As atoms of the same elements (isotopes) have the same atomic number but different mass number; hence cannot be said to be the same in all aspects.
(3) Dalton's theory also suggested that when atoms react, they do so in fixed, simple whole number ratio. The knowledge of organic chemistry shows atoms do not always react in simple whole number ratios
There are several modifications to different postulations by scientists that have also occurred aside from this, hence the most correct answer is that "As scientists learned more, they modified the atomic model"
