Answer:
Described by a redox reaction below
Explanation:
Iron(III) oxide is an ionic compound, since it consists of a metal, iron, and a nonmetal, oxygen.
Ionic compounds are formed when metals lose their valence electrons in order to have an octet in their previous shell and donate them to nonmetal atoms, so that nonmetals fill their outer shell to have an octet.
As a result, positive ions (cations) and negative ions (anions) are formed. When iron reacts with oxygen, the following reaction takes place:

This is a redox (oxidation–reduction) reaction, since we have electron loss and gain. Four iron atoms lose a total of 12 electrons to obtain a +3 charge in the final compound, while 3 oxygen molecules gain these 12 electrons to become 6 oxide anions with a -2 charge.
ANSWER

EXPLANATION
Given that;
The two reactants are KBr and CaO
Double replacement reaction is a type of chemical reaction that occur when two reactants exchange cations and anions to yield new products.

Therefore, the resulting products of the given data are K2O + CaBr2
The correct answer is option B
Answer:
The element from Group 13.
Explanation:
Following trends of the periodic table, atomic radius of the elements increase going down from the right side and decrease on its way up diagonally to the left. (sry if u can't understand me)
The branch of chemistry that the chemist might use will be the branch of <em>organic chemistry</em>. This is because gasoline is an organic compound. We can say that a compound is organic if it contains a carbon atom. Gasoline is composed of long chains of alkanes (hydrocarbons with single bonds) ranging from 4 carbon atoms to 12 carbon atoms.
The number of moles of ethanol the chemist will use in the experiment involving 30g of ethanol is 0.65moles.
<h3>How to calculate number of moles?</h3>
The number of moles of a substance can be calculated by dividing the mass of the substance by its molar mass. That is;
no. of moles = mass ÷ molar mass
According to this question, a chemist will use a sample of 30 g of ethanol (CH3CH2OH) in an experiment. The number of moles can be calculated as follows:
Molar mass of ethanol = 12(2) + 1(5) + 17 = 46g/mol
no of moles = 30g ÷ 46g/mol
no. of moles = 0.65moles
Therefore, the number of moles of ethanol the chemist will use in the experiment involving 30g of ethanol is 0.65moles.
Learn more about moles at: brainly.com/question/1458253