Answer: By performing the flame test
Explanation:
The flame test can be performed by the teacher to visually identify the substance in the solution. The metals give a characteristic color on burning. The heat of the flame causes the excitation of the electrons present in the metal ions this leads to release of energy along with the emission of visible wavelength of light. This visible light can be observed by human eye. For example, the copper produces the blue color in flame, barium gives green flame, and sodium gives yellow flame.

Here we go ~
Energy difference btween the two electronic states can be expressed as :

[ h = planks constant,
= frequency ]




Answer:
a. Polar
b. Polar
c. Non-polar
d. Non-polar
Explanation:
a.
, hydronium cation contains a positive charge. Just as any other ion, it is polar, as it has a net charge.
b.
has the same shape as water. There are two lone pairs on sulfur atom which produce an overall dipole moment in this molecule, the bent structure is polar.
c.
is non-polar, as the central atom, phosphorus, doesn't contain any lone pairs, all the dipole moments cancel out: two dipole moments in the vertical plane, P-Cl, and three P-Cl dipoles in the horizontal plane within a trigonal bipyramidal shape.
d.
is non-polar, since it's a tetrahedral molecule with no lone pairs on carbon atom, all four C-F dipole moments cancel out to yield a net 0 dipole moment.
1: a, 2:a, 3:a, 4:c, 5:d, 6:d, 7:c;
It is a covalant bond. Because any compound made up of nonmetals will be covalant. Compounds made up of a non metal and metal willl form a ionic compund. :)