Science Common Sense

1325 - What is the acidity and alkalinity of metal and non-metal oxides in aqueous solutions, and how do acidic solutions react with metals and marble?

Let's break it down in simple terms:

Metal and Non-Metal Oxides:

When metals and non-metals react with oxygen, they form oxides. In water, these oxides can be acidic or alkaline.

• Metal Oxides: Most metal oxides are alkaline (or basic) in water. They can turn pH indicators blue or green.
• Non-Metal Oxides: Non-metal oxides are acidic in water. They can turn pH indicators red or pink.

Examples:

• Metal oxides: Calcium oxide (CaO) is alkaline. Sodium oxide (Na2O) is also alkaline.
• Non-metal oxides: Carbon dioxide (CO2) and sulfur dioxide (SO2) are acidic.

How Acidic Solutions React with Metals:

When an acidic solution touches a metal, it can cause the metal to react and lose its electrons (oxidize). This is called corrosion. The acid will dissolve some of the metal and make it disappear.

How Acidic Solutions React with Marble:

Marble is mostly made of calcium carbonate (CaCO3). When an acidic solution meets marble, the acid (like vinegar or lemon juice) will react with the calcium carbonate, making carbon dioxide gas (CO2). This can create bubbles and make the marble look rough or etched.