Answer:
The correct option is C.
In a tightly closed container in a dry and well-ventilated place
Explanation:
Hydrogen peroxide should be store in a tight closed container and ventilated area because it is an oxidizing agent and it's has oxidizing characteristics. If to is exposed or the bottle lid is broken and exposed it can react and liberate oxygen and heat. It can react with the air and chemical it is exposed with. This will make it to be less effective and there will be a change in it's composition.
Answer:
Dmitry Mendeleev
Explanation:
Around 1869 a Russian scientist, Dmitry Mendeleev formed what is now known as the periodic table or chart. The Mendeleevian periodic table was based on the atomic weights of elements using the periodic law. The periodic law states that "chemical properties of elements are a periodic function of their atomic weights".
The modern periodic table was re-stated by Henry Moseley in the 1900s. He changed the basis of the periodic law to atomic masses.
There are 4 significant figures(3050)
The wording of your question doesn't quite make sense, but a mole of an element has the same mass in grams as a single atom of that element has in amu. The mole is defined as 6.02 x10^22 things, whether they be atoms or molecules or even moles! 6.02x10^22 atoms of carbon has a mass of 12.01 g, and a single atom of carbon has a mass of 12.01 amu. Hope this helps!
