C) 179 amu. Hf or hafnium is an element having an atomic number of 72. It is a transition metal <span>with at least </span>34 isotopes, five of these stable isotopes have an atomic mass ranging from of 176 amu to 180 amu. Getting the average atomic mass requires knowledge on the % abundance of the stable isotopes, and then getting the weighted average.
Answer:
A Neutron and a Hydrogen Atom
Explanation:
Hydrogen atom having an atomic mass of 1.008 amu consists of one proton and one electron. Hence, the +ve and -ve charges cancels out and makes the hydrogen atom a neutral specie.
Also, we know that neutron is neutral sub particle while, proton and electron are positively and negatively charged respectively. Therefore, a neutral neutron having no charge becomes equal to hydrogen atom having zero charge due to cancellation of both +ve and -ve charges.
Density is mass/volume so if you double the mass you would also double the volume which means density would stay the same. Density is the amount of of matter in a given area and it is constant for the substance regardless of differences in mass or volume.