The velocity of the gas is inversely proportional to the square root of the molar mass of the gass. Heavier molecules tend to travel slow compared to light molecules. Among these, He has the lowest molar mass of 4 g/mol hence this element has the greatest velocity among all molecules given.
Density is an intrinsic property, so it is independent of the amount of substance present: one gold coin would have the same density as a solid gold boulder.
So if the density of gold is 19.3 g/cm³, the density of a bar of gold and the pieces into which the bar is cut would all be 19.3 g/cm³.
Correct, Was that a question.
Answer:
I guess 3 to be honest and that's what I think
Answer:
Below are the statements which are true about the structure of the periodic table:
B: The inner transition elements are placed at the bottom of the periodic table for easy viewing.
D: The distribution of electrons in energy levels is responsible for the shape of the periodic table.
Explanation:
Point A:
As we know that in a periodic table there are 7 period s and 18 groups. So, the number of periods is evidently lesser than the number of groups. But the shape of periodic table is regular and rectangular so point A is false.
Point B:
The inner transition elements or -f block elements are put at the bottom for easy viewing. These are the elements that have the valence electrons only in the f-orbital's. Therefore, they are placed separately at the bottom side of the table so that they can be easily viewed or studied from there. So, point B is true.
Point C:
If we talk about option C, then it is very clear and true that considering a rectangular shape of the periodic table, the groups are vertically arranged and periods are horizontally arranged, therefore it is false.
Point D:
Atoms of all elements have definite electronic distribution in different energy levels like s, p d or f. This is a very prominent feature of periodic tale that elements are divided in specific blocks, s, p, d and f based on their electronic configurations. Therefore, it is true.
Point E:
We also know that no. of metals in a periodic table are more than the no. of non metals like almost 91 out of 118 elements are metals in periodic table. Therefore, the point E "Nonmetals take up more than half the area of the periodic table." is false.
Hope it helps!