What happened to fluorine when it obtains an outer shell

The image seems to be behind the mirror, but nothing is really there.just took the test.

Answer : option b) two grams of hydrogen react with one gram of oxygen to form two grams of water.explanation :

the equation for synthesis of water is as follows;

here two moles of hydrogen are used with one mole of oxygen which gives one molecule of water as a product. but shana misinterpreted 2 moles as 2 grams in this equation.

My best guess is that most of the earth would freeze causing an almost ice age like catastrophe

Most elements have more than one naturally occurring isotope. as you learned previously, the atoms of those isotopes have the same atomic number (number of protons), making them belong to the same element, but they have different mass numbers (total number of protons and neutrons) giving them different atomic masses. so which mass is put on the periodic table for each element? is it the most common isotope’s mass? the heaviest mass? this activity will answer that question.