Electron microscopes differ from light microscopes in that they produce an image of a specimen by using a beam of electrons rather than a beam of light. Electrons have much a shorter wavelength than visible light, and this allows electron microscopes to produce higher-resolution images than standard light microscopes
Energy can accomplish work
Electronegativity of an element decreases as we move down a group on the periodic table and electronegativity increases while moving from left to right across a period on the periodic table.
Explanation:
- The electronegativity increases as we move from left to right across a period because from left to right across a period, the nuclear charge is increasing Hence the attraction for the valence electrons also increases.
- As we move down a group, the atoms of each element have an increasing number of energy levels. The distance between the nucleus and valence electron shell increases and reduces the attraction for valence electrons. Hence electronegativity decreases as we move from top to bottom down a group.
Answer:
Benzoic acid is the stronger acid
Explanation:
Weak acids do not dissociate completely in the solution. They exists in equilibrium with their respective ions in the solution.
The extent of dissociation of the acid furnising hydrogen ions can be determined by using dissociation constant of acid (
).
Thus for a weak acid, HA

The
is:
![K_a= \frac{[A^-][H^+]}{[HA]}](https://tex.z-dn.net/?f=K_a%3D%20%5Cfrac%7B%5BA%5E-%5D%5BH%5E%2B%5D%7D%7B%5BHA%5D%7D)
The more the
, the more the acid dissociates, the more the stronger is the acid.
Also,
is defined as the negative logarithm of
.
So, more the
, less is the
and vice versa
All can be summed up as:
The less the value of
, the more the
is and the more the acid dissociates and the more the stronger is the acid.
Given,
of acetic acid = 54.7
of benzoic acid = 54.2
of benzoic acid <
of acetic acid
So, benzoic acid is the stronger acid.