<span>Molality(m) or molal concentration is a measure
of concentration and it refers to amount of substance in a specified amount of
mass of the solvent. Used unit for molality is mol/kg which is also
sometimes denoted as 1 molal. It is equal to the moles of solute (the substance
being dissolved) divided by the kilograms of solvent (the substance used to
dissolve).</span>
Molarity(M) or molar concentration is also a
measure of concentration and represents the amount of substance per unit volume
of solution(number of moles per litre of solution. Used unit for molarity is
mol/L or M. A solution with a concentration of 1 mol/L is equivalent to 1 molar
(1 M).
Molality is preferred when
the temperature of the solution varies, because it does not depend on
temperature, (neither number of moles of solute nor mass of solvent will be affected
by changes of temperature), while molarity changes as temperature changes(volume
of solution changes as temperature changes).
Explanation:
- As it is given that boiling point of propanamide is very high. So, reason for this is that easy formation of hydrogen bonds which are strong enough that we have to provide large amount of heat to break it.
As in 
, the hydrogen atoms which are present are positive in nature. Due to this they are able to form hydrogen bonds with the neighboring oxygen atom.
Hence, these bonds are so strong that high heat needs to given to break them.
- A propanoic acid contain carboxylic group as the functional group. So, this group is also able to form hydrogen bonding as it forms a hydrogen bond between an acid group and hydroxyl group of neighboring molecule.
Hence, it will also require high heat to break the bond due to which there will be increase in boiling point.
- In propanal, there is presence of aldehyde functional group and three carbon atoms chain which will not form strong bonding with the hydrogen atom of CHO. Due to this there will exist weak Vander waal's force that is not at all strong enough.
As a result, less energy will be needed to break the bonds in propanal. Hence, it has very low boiling point.
A) Polar (Cl is more electronegative than Si)
b) Nonpolar (Both atoms have the same electronegativity)
c) Ionic (Ionic bonds happen between a metal and a nonmetal)
d) Nonpolar (Hydrogen and carbon have about the same electronegativity) this is a common nonpolar bond)
You can identify the type of bon by looking at what is being bonded (nonmetal or metal) and the placement of the elements on the periodic table (electronegativity increases going up a group and going from left-right across a period).
Protons: <span>The mass of the proton is about 1,840 times the mass of the electron and slightly less than the mass of the neutron.
Electrons: </span><span>Electrons are arranged around the nucleus of atoms in regions called electron clouds or electron orbits.
Neutrons: </span><span>A neutron is one of two particles found inside the nucleus (central part) of an atom. The other particle is called a proton. Electrons are particles that move around an atom outside the nucleus.</span>
