Give the chemical symbol for one element with an electron configuration that ends with np2, where n is any principal quantum number

Remember any electronic configuration ending on np² means that it has a complete ns² orbital filled, So, the electronic configuration can be written as,

                                           ns², np²
Now,
       Let suppose n = 2, so the electronic configuration will be

                                          1s², 2s², 2p²

As n = 2 is the valence shell, so it belongs to 2nd Period.

As there are 4 electrons in valence shell, so, Group number is 4-A.

Looking at Period 2 and Group-IV A, the element found is,

                                              Carbon

If it releases 5 tons a day and there are 7 days a take that answer and multiply by 5 percent (0.05) to find the amount released in one week. leave a comment if you need more .