0.249 g of a common diatomic gas occupies a volume of 250. ml at 120°c and 760 mmhg. using a periodic table, what is the identity of this element?

Forests and meadows are often cut down to make way for farms or large number of new homes. what are some of the elements of ecosystems that are lost when plants in these areas are removed?

What volume of a 2.00 m stock solution of naoh is needed to prepare 150. ml of 0.40 m solution?

Choose all the answers that apply. fluorine (f) has an atomic number of 9 and an atomic weight of 18.99. fluorine has a. 9 protons b. 10 neutrons c. 18 electrons d. an atomic mass of 19 e. at least one isotope