The units of molar mass is g/mol that is the letter B.
Marie curie worked as a governess and she was awarded noble prize for her discoveries.
Explanation:
When Marie curie worked as a governess for three years her employer allowed her to teach reading to the children of peasant workers at his beet sugar factory. This was banned under Russian rule. During that time she studied chemistry lessons from her father by mail.
Marie curie was awarded the Noble prize in chemistry for her discoveries and studies of elements radium and polonium. She is the only women who is awarded the Noble prize twice.
She made her first research into the treatment of tumors with radiation and founded a Curie institutes, that are important medical research centers.
What Are Living Rocks? Rocks themselves are not alive. But in a coral reef rock-like lime substance is continually produced from the skeletons of dead rock corals and the shells of mussels and other creatures which are bound together by sponges and calcareous algae.
but tbh I have no idea lol!
Answer:
An alkali metal present in period 2 have larger first ionization energy.
Explanation:
Ionization energy:
The amount of energy required to remove the electron from the atom is called ionization energy.
Trend along period:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required.
Trend along group:
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
As the size of atom increases the ionization energy from top to bottom also decreases because it becomes easier to remove the electron because of less nuclear attraction and as more electrons are added the outer electrons becomes more shielded and away from nucleus. Thus alkali metal present in period 2 have larger ionization energy because of more nuclear attraction as compared to the alkali metal present in period 4.
