Y7 Chem BT 7_2 Atomic Notation & Chemical Formula

When electron jumps from higher energy level to lower energy level:

• - Energy is emitted

• When an electron jumps from a lower energy level to higher energy level:

• - Energy is absorbed

Answer explanation

• - Energy is emitted

• - Energy is absorbed

When electron jumps from higher energy level to lower energy level:

• - E............ is e............

• When an electron jumps from a lower energy level to higher energy level:

• - E.................. is a..............

Answer explanation

• - Energy is emitted

• - Energy is absorbed

Isotopes means same number of protons & electrons but different numbers of neutrons

Isotopes means ......................

(2 answers)

• same number of photons & electrons

• same number of neutrons

• same number of protons & electrons

• different number of neutrons

In an ionic compound, after Combination, the molecules remains neutral:

• - the two electrically charged ions balance each other.

Answer explanation

• - the two electrically charged ions balance each other.

In an ionic compound, after Combination, the molecules remains neutral:

Answer explanation

• - the two electrically charged ions balance each other.

What is the correct word equation for the following reaction.

nitric acid react with potassium hydroxide to produce ________ and water

• potassium sulfate

• potassium oxide

• potassium nitrate

• nitric hydroxide

Atomic number is 12 , the valency of Magnesium is 2 : Reason:

Magnesium with the atomic number 12 has the electronic configuration (2.8.2).

It lose 2 electrons to become electronic configuration (2.8),

It has complete outer Octet

Atomic number is 12 , the valency of Magnesium is 2 : Reason:

Magnesium with the atomic number 12 has the e................. con........... of (2. . ).

It lose 2 electrons to become electronic configuration of (. . ),

It has complete outer O............

When atoms accepts electrons, it lose its

• neutrality

• protons

• electrons

• neutrons