Answer:
Option (A)
Explanation:
Radioactivity is defined as a process in which an unstable atomic nucleus decays continuously and after a specific period of time changes into a much more stable element. During this time of decay, the nucleus emits charged particles (energy) which are known as the α, β and γ particles. These are often emitted in the form of electromagnetic energy and are very dangerous to health.
The radioactive elements decay at a certain rate which is commonly known as the half-life. Half-life is basically defined as the time required by a radioactive substance to decay half of its initial composition.
Thus, the correct answer is option (A).
Answer:
Explanation:
A neutral titanium atom will have 22 electrons. Therefore, its electron configuration will be 1s2 2s2 2p6 3s2 3p6 4s2 3d2.
Answer:
100g / (5.2g/cm3)
= 100g / (5.2g / 1cm3)
= 100g x 1cm3 / 5.2 g
= 19.2 cm3
Since 1 cm3 = 1 ml, your answer is 19.2 ml.
Answer:
Higher concentration to an area of lower concentration
Explanation:
When you open a perfume bottle at a corner of a room, after a while, its fragrance can be perceived across a distance at the other end of the room. This is because, molecules of the compound in the fragrance have moved from the area of higher concentration in the perfume bottle, across a concentration gradient to a region of lower concentration at the other end of the room. This is diffusion.
An element with 8 valence electrons is Neon (Ne).
Ps: Any element under group 18 has 8 valence electrons except for Helium (He).
