Density=mass/volume
Data:
mass=890 g
volume=100 cm³
Density=890 g/100 cm³=8.9 g/cm³
answer: the density of the copper is 8.9 g/cm³
Answer:
Hey!
Your answer is element A
Explanation:
Using the graph, the element A's emission of radioactive particles ends approximately after 6 years...
A HALF-LIFE IS "HALF" OF THAT TIME PERIOD!
So if the radiation goes for 6 years the half-life is 6 divided by two which gives you 3 years!
The rest however have a longer half-life...
Because they all end at 14 yrs so their half-life in 7 years!
HOPE THIS HELPS!!
Actually Welcome to the concept of Atomic Structure.
Since, We all know that, To draw any Electron-Dot Structure, we always have to know the exact Number of valence or free electrons of any atom or molecule, hence
The Correct Answer is :-
D. Number of valence electrons.
