The atomic mass of hydrogen

A hydrocarbon was found to contain approximately 75% carbon and 25% hydrogen by mass. Calculate the empirical formula of the hydrocarbon, assuming relative atomic masses of carbon and hydrogen as 12 and 1.

The atomic mass of sodium is 23 u. What is the number of moles in 46 g sodium?

What is called relative atomic mass of an element?

Estimate the average mass density of a sodium atom assuming its size to be about 2.5 A- (Use the known values of Avogadro’s number and the atomic mass of sodium). Compare it with the density of sodium in its crystalline phase: 970 kg m^(-3) . Are the two densities of the same order of magnitude? If so, why

How can you determine the atomic mass of an unknown metal if you know its density and the dimension of its unit cell? Explain.

Name the various series of hydrogen atoms.

Define the atomic mass unit.