Iron III ion is an iron ion with a +3 charge. If iron bonded with oxygen, it would form Fe2O3 which is rust. In this case, the oxidation number on Fe is +3 and it is -2 on oxygen. This would be called iron (III) oxide.
<span>The oxidation number of an ion times the number of the ions must equal zero when added together in a molecule with no charge. In this case, there are 2 iron molecules and each has a positive 3 charge. 2x3=6. There are three oxygen molecules each with a negative 2 charge. 3x-2=-6. 6+-6=0</span>
Current = (voltage) / (resistance)
= (12 V) / (2.5 ohms)
= 4.8 Amperes
Answer:
d. Two soccer balls that are touching each other
Explanation:
Let
be the mass of a tennis ball,
is the mass of a soccer ball.
As the mass of a soccer ball is more than the mass of a tennis ball, so

Let
be the distance between the centers of both the balls near each other and
be the distance between the centers of both the balls touching each other.
So, 
The gravitational force, F, between the two objects having masses M and m and separated by distance d is

Where G is the universal gravitational constant.
As, the gravitational force is directly proportional to the product of both the masses and inversely proportional to the square of the distance between them, so selecting the larger mass (
, soccer ball) separated by a lesser distance (
, touching) to get more gravitational force.
Therefore, there will be a larger gravitational force between them when two soccer balls touching each other.
Hence, option (d) is correct.
Answer:
P=I^2*R=400R where R is the resistance of the wire
Explanation: