Answer: Atomic mass is associated with the number of neutrons and protons that are present in a particular nucleus of an element. Atomic number is usually the number of protons present in an element's nucleus. It is the average weight of an element. It is the total number of nucleons in the atom's nucleus.
Assuming there were errors in atomic masses, Mendeleev placed certain elements not in order of increasing atomic mass so that they could fit into the proper groups (similar elements have similar properties) of his periodic table.
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It is a moderate conductor of electricity, and in nature it is a dark indigo blue mineral. Density: 4.6g/cm^3. insoluble in water. melting point above 500 degrees C.
Its a change in state of solid to liquid
the reason is that in a solid state the molecules have little kinetic energy to move and so they have restricted movement and so it remains solid
once heat is applied the molecules gain enough energy to move and so they turn into a liquid and move according to the laws of physics
hope that helps
Answer:
a, and f.
Explanation:
To be deprotonated, the conjugate acid of the base must be weaker than the acid that will react, because the reactions favor the formation of the weakest acid. The pKa value measures the strength of the acid. As higher is the pKa value, as weak is the acid. So, let's identify the conjugate acid and their pKas:
a. NaNH2 will dissociate, and NH2 will gain the proton and forms NH3 as conjugate acid. pKa = 38.0, so it happens.
b. NaOH will dissociate, and OH will gain the proton and forms H2O as conjugate acid. pKa = 14.0, so it doesn't happen.
c. NaC≡N will dissociate, and CN will gain a proton and forms HCN as conjugate acid. pKa = 9.40, so it doesn't happen.
d. NaCH2(CO)N(CH3)2 will dissociate and forms CH3(CO)N(CH3)2 as conjugate acid. pKa = -0.19, so it doesn't happen.
e. H2O must gain one proton and forms H3O+. pKa = -1.7, so it doesn't happen.
f. CH3CH2Li will dissociate, and the acid will be CH3CH3. pKa = 50, so it happens.