Which allotrope of carbon is considered the hardest material known?

Which family on the periodic table contains elements that already have the octet in their valence energy level? a:family 1 b:family 13 c:family 15 d:family 18?

The mass of h2 produced by reaction of 1.80 g al and 6.00 g h2so4 is 0.112 g. what is the percent yield?

What is the formula of the hydride formed by nitrogen?

what temperature will 215 mL of a gas at 20°C and 1 atm pressure attain when it is subject to 1.5 atm of pressure?

Will a helicopter work in a vacuum

To what chemical reaction class does this reaction belong? 2 mg (s) + o2 (g) 2 mgo (s)

Which best illustrates how particle arrangement changes when solids change into liquids

Express in scientific notation (6.0x10^4) (3.1x10^-1)

How do you measure the mass of a liquid?

Given the following information, calculate the mass for B-11. B-10 has a natural abundance of 19.9 percent, while B-11 has a natural abundance of 80.1 percent. The mass of B-10 is 10.013 amu.