Question 1:
Hydronium ions contain a positive charge.
Explanation:
Any ions that formed via losing electrons or giving it to surrounding contain a positive charge that the number of protons is more than that of electrons.A hydronium ion is represented as (H₃O⁺). It can be formed via the dissociation of water to form hydronium can be seen here: 2 H₂O ⇌ OH⁻ + H₃O⁺.It is also can be formed when something like acid (HCl) donates a proton, H+, to a water molecule. The H+ will simply bond to water molecules with one of the two lone pairs of electrons around.
HCl + H₂O → H₃O⁺ + Cl⁻
Question 2:
Ammonium hydroxide is the best to neutralize sulfuric acid.
Explanation:
Many bases can be used to neutralize sulfuric acid such as NaOH, sodium carbonate, sodium bicarbonate, calcium hydroxide, ammonium hydroxide, …etc.Ammonium hydroxide is one of the best choices to neutralize sulfuric acid because it is not strong base. Also, ammonium compounds are soluble in water, so no color change, and no precipitate will be observed.The neutralization reaction between ammonium hydroxide and sulfuric acid: 2 NH₄OH + H₂SO₄ ⟶ (NH₄)₂SO₄ + 2 H₂O.
Question 3:
Raisins in cereals are example of heterogeneous mixture.
Explanation:
Heterogeneous mixture is the mixture that is not uniform in composition and properties. We can identify and see the different components in the mixture.Raisins are the dried fruit of a certain type grape and they are different and can not be mixed in cereals to be homogeneous, so raisins in cereals are example of heterogeneous mixture.
Question 4:
Sugar dissolves in water because both are made up of polar molecules.
Explanation:
We have a rule that “like dissolves like”. Polar molecules dissolve the polar salts and non-polar molecules dissolves the non-polar type.Sugar is polar molecules that contains in its structure C-O-H. They have difference in electronegativity that make it forms hydrogen bonds between its molecules and thus dissolves in the polar solvent water.
Question 5:
Steel is an alloy.
Explanation:
Alloy can be defined as a combination of adding two or more metals or components to enhance its physical properties and its overall performance that of each single metal or component forming the alloy.Steel is an alloy composed of iron (the main component) and carbon (sometimes using phosphorus, silicon, manganese, chromium, …etc.) in very little proportion. It is characterized by its high tensile strength and low cost.So, it is widely used in buildings, infrastructure, tools, ships, automobiles, machines, appliances, and weapons.
Kindly find the answers of the remaining questions in the attached images.
Image 1 (Q6: Q9)
Image 2 (Q10: Q12)
Image 3 (Q13: Q16)
Image 4 (Q17: Q20)
Image 5 (Q21: Q24)
