I’m pretty sure it’s true
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".
Explanation:
Water is a polar solvent as the hydrogen and oxygen atom has large difference in their electronegativities.
Oxygen atom is highly electronegative as compared to hydrogen atom therefore, it pulls the electrons of hydrogen atom closer towards itself.
As a result, two poles will create forming a partial positive charge on the hydrogen atom and partial negative charge on the oxygen atom.
Thus, we can conclude that high electronegativity difference between oxygen and hydrogen is the cause of polarity in water molecules.
Answer:
The scientist is observing an intensive property of a superconductor.
Explanation:
An intensive property is a bulk property of matter. This means that an intensive property does not depend on the amount of substance present in the material under study. Typical examples of intensive properties include; conductivity, resistivity, density, hardness, etc.
An extensive property is a property that depends on the amount of substance present in a sample. Extensive properties depend on the quantity of matter present in the sample under study. Examples of extensive properties include, mass and volume.
Resistance of a superconducting material has nothing to do with the amount of the material present hence it is an intensive property of the superconductor.
4Li + O₂ = 2Li₂O
Li : Li₂O = 4 : 2 = 2 : 1
2 : 1
x : 4
x=4*2/1=8 mol
D) 8