Why does a weather balloon filled with Helium rise? (Refer to "Densities of Common Substances" table.)

a) Its density is greater than air.

b) Its density is less than air.

Qualitative or quantitative data. the taste of an apple:

The number of nucleons in an atom is the atom's (atomic, mass) number.

A syringe contains 0.65 moles of he gas that occupy 900.0 ml. what volume (in l) of gas will the syringe hold if 0.35 moles of ne is added?

According to the periodic trend, which of the following is most likely to have the lowest electronegativity? I Rb Y Pd

Has a total of twelve $5 and $10 bills in his wallet. He has 5 times as many $10 bills as $5 dollar bills. How many of each does he have?

What is the general form for the simplest type of acid-base reaction?

Which element has a larger atomic radius than sulfur? chlorine cadmium fluorine oxygen

Which of the following procedures is used when refining petroleum? Increase the temperature of the oil. Decrease the temperature of the oil. Increase the pressure of the oil. Decrease the pressure of the oil.

What is the mass of calcium in 2.3•10^23 molecules of calcium phosphate

How many metaloides are found on the periodic table