Hydrobromic acid is added to a solution of lead(II) nitrate. Predict the products, and write a balanced equation for this reaction. Phases are not necessary.

2HBr + Pb(NO₃)₂ → PbBr₂ + 2HNO₃

Explanation:

Hydrobromic acid (HBr), reacts with lead (II) nitrate (Pb(NO₃)₂) producing Lead(II) bromide (PbBr₂) and nitric acid (HNO₃). The reaction is:

HBr + Pb(NO₃)₂ → PbBr₂ + HNO₃

This reaction is unbalanced. You can see in products 2 Bromides but in reactants just 1. And in reactants 2 NO₃ but as product just 1. Thus, you can balance the equation, thus:

2HBr + Pb(NO₃)₂ → PbBr₂ + 2HNO₃

And this equation is the answer of your question!

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.