Answer:
See Explanation
Explanation:
Elements in group fourteen are mostly known to form compounds in which there are four electron domains leading to a tetrahedral electron domain geometry.
However, the presence of lone pairs affects the shape of the molecule. SnCl3− has four electron domains, three of them are bond pairs while one is a lone pair. The shape of the molecule is based on a tetrahedron, however the observed geometry is trigonal pyramidal due to the presence of the lone pair. Its bond angle is now less than the predicted 109 degrees.
For physics the answer is 47500
solution:
The quoted atomic mass on the Periodic Table is the WEIGHTED average of the individual isotopic masses. The higher the isotopic percentage, the MORE that isotope will contribute to the isotopic mass. For this reason, most masses that are quoted on the Table are non-integral.
By way of example we could look to the hydrogen atom. The VAST majority of hydrogen atoms (in this universe) are the protium isotope. i.e. 1H, whose nuclei contain JUST the defining proton. There is a smaller percentage (>1%) of hydrogen atoms WITH one NEUTRON in their nuclei to give the deuterium isotope. i.e. 2H, and because this is relatively cheap, and easily incorporated into a molecule, deuterium labelling is routinely used in analysis.
And there is even a smaller percentage of hydrogen atoms with TWO NEUTRONS in their nuclei, to give the tritium isotope. i.e. 3H. The weighted average of the isotopic percentages gives 
The primary greenhouse gases are water vapor, carbon dioxide, methane, nitrous oxide, and ozone. So, the correct answer among these options is water vapor, that is considered to be a greenhouse gas.
Answer:
B) They will react because X and Y can share two pairs of electrons to become stable
Explanation:
The electron configurations of two elements x and y are given :
X: 1s2 2s2 2p6
Y: 1s2 2s2 2p6 3s2 3p6
The statement that is true for both the elements is that, they both will react as they both can share two pairs of electrons to become stable.
To become stable the outermost shell or p orbital should have 8 electrons, so element X can gain 2 atoms to become stable.
Element Y can also react as it can also share two atoms to fulfill its 3p orbital and will stable.
Hence, the correct option is "B".
