Explanation

 the oxides of electropositive elements are generally basic.

Electropositive elements are those that tend to lose electrons and form positive ions.

When these elements react with oxygen, they form oxides that exhibit basic properties.

These oxides can react with water to form hydroxides and are capable of neutralizing acids, indicating their basic nature.

Examples of oxides of electropositive elements include:

• Sodium oxide (Na2O)
• Magnesium oxide (MgO)
• Calcium oxide (CaO)
• Potassium oxide (K2O)

Explanation

The height of the peak in a mass spectrum shows the relative abundance or intensity of ions with a specific mass-to-charge ratio (m/z) in the sample.

In simpler terms, a taller peak indicates a higher abundance or intensity of ions with that particular mass-to-charge ratio compared to other ions in the sample.

Explanation

• Sublimation is the process by which a solid substance transitions directly into a gas or vapour, without going through the liquid phase, and then condenses back into a solid.
• Examples include iodine, dry ice, and naphthalene.

Explanation

The incorrect statement is: Metals are dull and soft.

Metals are typically:

• Solid at room temperature
• Have high melting and boiling points
• Good conductors of heat and electricity
• Shiny (although some metals may have a dull appearance due to oxidation or other surface treatments)
• Ductile (can be drawn into thin wires or sheets)
• Malleable (can be pounded into shape without breaking)

Explanation

• The pH value of pure water at room temperature is 7.
• This is because pure water is neutral, meaning the concentration of hydrogen (H3O+) and hydroxide (OH-) ions are equal.

Explanation

The chemical formula CH₃COOH represents acetic acid, a weak organic acid commonly found in vinegar.

Key Information:

Common Name: Acetic acid (systematic name: ethanoic acid).

Properties:

• Weak acid (partially dissociates in water).
• Pungent smell, sour taste (vinegar contains ~4–8% acetic acid).

Explanation

Fluorine (F) is the most reactive nonmetal and the most electronegative element.

It reacts violently with almost all elements (e.g., water, metals, glass).

Explanation

Secondary cells are rechargeable, meaning they can be recharged and used multiple times, unlike non-rechargeable primary cells. 

Explanation

Explanation

One mole of any compound contains 6.02x10^23 molecules of that compound. 

In one molecule of SO2, there is one sulfur atom and two oxygen atoms. 

Therefore, one mole of SO2 contains 6.02x10^23 sulfur atoms.