Answer:
Mass = 14.876 g
Explanation:
Given data:
Volume of gold = 0.77 cm³
Mass of gold = ?
Solution:
Density of gold from literature is 19.32 g/cm³
Formula:
d = m/v
d = density
m = mass
v = volume
by putting values,
19.32 g/cm³ = m/ 0.77 cm³
m = 19.32 g/cm³ × 0.77 cm³
m = 14.876 g
CH2OHCH2OH is a
general example of a polyhydroxyl alcohol. A polyhydroxyl alchol is one in which
there are two hydroxyl groups present in the substance. The –OH group attached
to both the carbon atoms.

Here we go ~
Energy difference btween the two electronic states can be expressed as :

[ h = planks constant,
= frequency ]




Answer:
A calculator has an endifiite shape because all of its atoms are touching each other
Let's eliminate these one by one.
The first pair would not be the same, as X would most likely be in group IA, and Y would be in group VIIA, because of their tendency to gain and lose electrons.
The second pair would also violate the same rule, but X would most likely be in group IIA, and Y would most likely be in group VIA.
The third pair would not be the same, as X is most likely in group VIIA, and since Y has eight valence electrons, it is most likely a noble gas.
The final pair has X with atomic number 15, making it phosphorous. Phosphorous wants to gain 3 electrons to have a full octet of 8 outer "valence" electrons, and Y would also like to gain 3 electrons. This means it is possible that the final pair would be in the same group.