4. Assign an oxidation state to the element whose atom is underlined in the following compound: AIH3 O Al: +5
O Al: -5
Ο Ο Ο
Al: -3
O Al: +3

The oxidation state of Al in is +3.

Explanation:

The number attained by an atom or substance due to loss or gain of electrons is called oxidation state.

For example, in it is known that the oxidation state of hydrogen is -1 as aluminum is a cation so it cannot have an oxidation state as 'minus'.

Whereas hydrogen has the property to act both as a cation and an anion.

Let us assume the oxidation state of Al is x in the compound .

Hence, oxidation state of Al is calculated as follows.

This means that the oxidation state of Al in is +3.

Thus, we can conclude that oxidation state of Al in is +3.

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

the answer is barium and copper bromide