Which statements describe properties that are unique to metalloids? Check all that apply.

Metalloids are shiny.

Metalloids are semiconductive.

Metalloids are solid.

Metalloids are amphoteric.

Metalloids are brittle

The ""size"" of an atom is sometimes considered to be measured by the radius of the sphere that contains 90% of the charge density of the electrons in the outermost occupied orbital.

How much heat is absorbed/released when 25.00 g of NH3 (g) reacts in the presence of excess O2 (g) to produce NO (g) and H2O (l) according to the following chemical equation? 4 NH3 (g) + 5 O2 (g) → 4 NO (g) + 6 H2O (l) ΔH° = 1168 kJ

Formula mass of (NH4) 2SO4?

Why does the fact that Americans are using less fertilizer not indicate a decline in American farming?

What is silica sand used for?

If an object mass is 50 g, and it's volume is 10 cubic cm, what is it's density

According to one acid-base theory, the H2O (l) molecules act as a ...

What does H2 stand for

How the model of an atom has changed over time because?

Which of the following conditions indicate a basic solution at 25°C? a. POH=11.21 b. pH=9.42 c. [OH-]>[H+] d. [OH]> 1.0 x 10^-7 M