They are called groups or family. Hope this helps
Hey there
Thats easy
Precipitation occurs when cations and anions in aqueous solution combine to form an insoluble ionic compound called precipitation. So, you can refer to a solubility chart or draw polar/nonpolar lewis structures, that might be helpful.
Remember water is polar so polar molecules will dissolve in water
I believe it’s c because if you really read and close read it will make more sense
Answer:
Therefore the density of the sheet of iridium is 22.73 g/cm³.
Explanation:
Given, the dimension of the sheet is 3.12 cm by 5.21 cm.
Mass: The mass of an object can't change with respect to position.
The S.I unit of mass is Kg.
Weight of an object is product of mass of the object and the gravity of that place.
Density: The density of an object is the ratio of mass of the object and volume of the object.

[S.I unit of mass= Kg and S.I unit of m³]
Therefore the S.I unit of density = Kg/m³
Therefore the C.G.S unit of density=g/cm³
The area of the sheet is = length × breadth
=(3.12×5.21) cm²
=16.2552 cm²
Again given that the thickness of the sheet is 2.360 mm =0.2360 cm
Therefore the volume of the sheet is =(16.2552 cm²×0.2360 cm)
=3.8362272 cm³
Given that the mass of the sheet of iridium is 87.2 g.

=22.73 g/cm³
Therefore the density of the sheet of iridium is 22.73 g/cm³.