D for sure hope this helps
Answer:
An atom of Al which has 13 protons and 10 electrons is Al cation (Al⁺³)
Explanation:
An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other.
For example,
Al atom has 13 protons and 13 electrons. The number of positive and negative charge is equal thus it will be neutral atom.
While the atom of Al which have 13 proton and 10 electron is not neutral. The positive charge is greater than negative by 3. Which means 3 electrons are lose by Al atom and form cation "Al⁺³".
Thus an atom of Al which has 13 protons and 10 electrons is Al cation (Al⁺³)
Apples turn brown when exposed to air because it undergoes aerial oxidation. Due to this, when the inside of the apple is exposed to the air containing oxygen and water, it turns brown. When apple is uncut, skin of the apple protects it from this process.
If the peeled apple in kept in the refrigerator, the oxidation reaction is greatly slowed down. This is because, rate of chemical reaction decreases with temperature. Hence, in refrigerator it would take several days for it to turn brown.
Answer
B. acid + base --> salt + water
Explanation
Acids are substances that dissolve in water to produce hydrogen ions, H+.A base is a substance that dissolves in water to produce hydroxide ions, OH-.In a chemical reaction of an acid and a base, the products are a salt and water.For example when hydrocholoric acid is added to sodium hydroxide, a salt namely sodium chloride is formed with additional water.
Answer:
B. Intermolecular forces are hard to overcome
Explanation:
A high boiling point indicates greater inter molecular forces between the molecules of the substance. Inter molecular forces is the force of attraction between the molecules of the substance, which has to be overcome or broken before the substance boils. Example, when water boils, the water molecule (H₂O) will be broken into hydrogen molecule and oxygen molecule.
Therefore, a high boiling point temperature indicates that intermolecular forces of the substance are hard to overcome.
B. Intermolecular forces are hard to overcome
