Question

When a magnesium ribbon is burnt in air, the ash formed is
\[1\]) Black
\[2\]) White
\[3\]) Yellow
\[4\]) Pink

Answer 1

Hint: We need to remember that in chemistry, periodic tables play a vital role. In the periodic table there are totally \[118\] elements. In the periodic table there are totally \[18\] columns and \[7\] rows. The columns are called groups. Hence, \[18\] groups in the periodic table. The rows are called periods. Hence, totally \[7\] period in the table. Magnesium is present in the second group and the oxygen is present in the sixteenth group of the periodic table.

Complete answer:
As we know, the atomic number of magnesium is \[12\]. It is one of the alkaline earth metals in the periodic table. It is present in the third period and second group in the periodic table. The symbol of magnesium is \[{\text{Mg}}\].
The atomic number of the oxygen is \[8\]. It is present in the second period and sixteenth group in the periodic table. The symbol of oxygen is \[{\text{O}}\].
\[{\text{2Mg + }}{{\text{O}}_{\text{2}}} \to {\text{2MgO}}\]
The initial mass of the magnesium is only dependent on the atomic weight of the magnesium atom. After magnesium is reacted with air to give magnesium oxide. When a magnesium ribbon is burnt in air, the ash formed is white. The colour of magnesium oxide is white.
According to the above discussion we conclude when a magnesium ribbon is burnt in air, the ash formed is white.

So, the correct answer is “Option 2”.

Note:
We need to know that the atomic number of the atom depends on the number of protons or the number of electrons. The atomic number of the atom is equal to the number of protons or the number of the electrons. The mass number of the atom depends on the number of protons and the number of neutrons. The mass number of the atom is equal to the sum of the number of protons and the number of neutrons in the atom. The oxidation reaction means addition of oxygen or the removal of hydrogen or the loss of electrons. The reduction reaction means addition of hydrogen or the removal of oxygen or the gain of electrons.