Answer:
Halogens have 7 valence electrons.
Explanation:
They are the most active non-metals including fluorine, chlorine, bromine, iodine, and astatine
In this case, according to the given information about the oxidation numbers anf the compounds given, it turns out possible to figure out the oxidation number of manganese in both MnI2, manganese (II) iodide and MnO2, manganese (IV) oxide, by using the concept of charge balance.
Thus, we can define the oxidation state of iodine and oxygen as -1 and -2, respectively, since the former needs one electron to complete the octet and the latter, two of them.
Next, we can write the following
, since manganese has five oxidation states, and it is necessary to calculate the appropriate ones:

Next, we multiply each anion's oxidation number by the subscript, to obtain the following:

Thus, the correct choice is Manganese has an oxidation number of +2 in Mnl2 and +4 in MnO2.
Learn more:
Answer:D the pressure increases
Explanation:
I think it's just water right..?
Answer:
It is a right triangle
Explanation:
We are given the directions in which a bird flew to make a triangle.
We are required to determine whether the triangle is right angle.
What is a right triangle?
- It is a triangle that has a right angle between the shorter sides or legs
- The triangle also obeys the Pythagoras theorem, such that the square of the two legs is equal to the square of the hypotenuse.
- Such that if the two legs are, a and b while c is the hypotenuse.
Then, a² + b² = c²
In this case;
Taking the legs as a= 21 yards and b = 72 yards and the hypotenuse, c = 75 yards.
Then we can determine whether it is a right triangle;
a² = 21² = 441
b²= 72² = 5184
c² = 75² = 5625
a² + b² = 5625
Therefore; a² + b² = c²
Hence, the triangle is right triangle.