Given :
Some compounds :
.
To Find :
Which of the following compounds has the most deshielded protons .
Solution :
Deshielded means nucleus whose chemical shift has been increased due to removal of electron density, magnetic induction, or other effects .
In simple words deshielding means the ability to shift protons .
Now , among Cl , I , Br and H . Cl is the most electron negative .
Therefore , deshielding will be more in 
.
Hence , this is the required solution .
Answer:
Robert Boyle
Explanation:
En muchos textos se suele considerar a Robert Boyle como el científico que introdujo en la Química un concepto de elemento diferente al empleado por los aristotélicos o por los alquimistas y que sirvió de antecedente al que formulara Lavoisier en 1789.
Answer:
Option A=> -NHCOCH3 and option C = -CH3.
Explanation:
The option A that is -NHCOCH3 is CORRECT because it possesses lone pair of electron with the exception of group 7A elements. It is this lone pair that is used in the Activation of the ring towards substitution. Other groups that falls into this group are; OCH3, alkyls and many others.
Option B that is -COOH is good group for withdrawal of electron through Resonance. Other examples are NO2, -CN and SO3H.
Option C falls to the same category as option A above that is Activation of the ring towards substitution.
Option D falls to the same category as option B above that is group for withdrawal of electron through Resonance.
When writing an ionic compound formula, a "molecular" form is used. The formula is made with allowance for ion charges.
For example,
Ca²⁺ and NO₃⁻ ⇒ Ca(NO₃)₂
Al³⁺ and SO₄²⁻ ⇒ Al₂(SO₄)₃
it is either "aweak acid or a lousy (or very weak) acid"
