Answer:
Dark matter makes up 85% of the mass of the universe. Dark matter is not directly observable because it doesn't interact with any electromagnetic wave. In the development of the universe, without dark matter, the universe will not function, move or rotate as it does now (this speculation led to the quest to find the anomaly of mass and energy in the known universe, eventually leading to the idealization of dark matter) and will not have enough gravitational force to hold it together. After the big bang,<em> the presence of dark matter and energy ensured that the newly formed universe didn't just float away, rather, it provided enough gravitational force to hold the universe while still allowing it to expand sufficiently</em>.
The development of the universe would have been different without the universe in the sense that the young universe won't have enough mass to hold it together, and the universe would have simply floated apart. The behavior of the universe would have been different from what we observe now, and some physical laws that applies now will not apply to the universe.
Alkenes on reaction with meta-chloroperoxybenzoic acid (MCPBA ) produces epoxides. When styrene is reacted with mCPBA it gives 2-phenyloxirane as shown below,
These 5 metals are: zinc,copper,tin,bronze,nickel
<h2>In the name, iron(III) oxide, the (III) represents: D) the electrical charge of iron</h2><h2>
Explanation:</h2>
To attain stability the chemical bond is formed .
Chemical bond
It is a kind of linkage that binds one atom with the other .
The atoms do so in order to attain stable noble gas configuration .
To form chemical bond they either:
Loose electrons : when atoms loose electrons they acquire positive charge which is equal to the number of electrons lost .
Gain electrons: After gaining electrons they acquire negative charge which is equal to the number of electrons gained by an atom.
share electrons : With sharing no charges are develop .
<em>In the above asked question when iron combines with oxygen it forms iron oxide : where iron looses 3 electrons and oxygen gains 2 electrons .That is the reason ,III here represents the electrical charge of iron</em>
Answer: Antoine Lavoisier.
He classified the elements into four groups: elastic fluids, nonmetals, metals and earths. Some of the called elementes were not really elements (light and heat). Others were compounds, e.g. hydrochloric acid.
