the very reactive gasses of the periodic table are called halogens.
Answer:
There are 3 bonding pairs of electrons
Explanation:
For every bond there is one bonded pair of electrons. NH₃ has three N-H bonds, so has three bonding pairs of electrons along with a lone pair of electrons
Answer:
B
Explanation:
First of all it is important to know that a half filled orbital is particularly stable. In phosphorus all the electrons occur singly in the 3p sublevel minimizing inter electronic repulsion hence it is more difficult to remove an electron from this energetically stable arrangement. In sulphur, electrons are paired in one of the 3p orbitals thereby lowering the energy of that level due to instability caused by interelectronic repulsion between two electrons in the same orbital.
Answer : The mass of 
is, 4.43 grams.
Explanation :
As we know that, when dissolve in water then it dissociates to give 2 mole of sodium ion 
and 1 mole of sulfate ion 
The chemical reaction will be:
Thus, the concentration of = 
First we have to calculate the moles of
Now we have to calculate the mass of
Molar mass of = 142 g/mol
Thus, the mass of is, 4.43 grams.
Solubility varies vastly. It depends on the solute, solvent, temperature, and pressure.
