Qadad

High school (ages 12+)
Making & Design

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/qadad

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the material classification?Waterproof lime plaster with pozzolanic additives
2. What is the primary geographic origin?Yemen
3. Why does Qadad use volcanic rocks?The volcanic rocks, called shash, react with lime to make the plaster very strong and water‑proof. They help the plaster stay solid for many years.
4. How long does it take for Qadad to set?Making Qadad can take more than a hundred days, and it can take over a year for the plaster to fully harden. This slow process helps it become very durable.

Slaked Lime: Calcium hydroxide, produced by reacting calcium oxide with water, serving as a binder in mortars and plasters.
Pozzolanic Reaction: A chemical reaction between siliceous or silico-aluminous materials and calcium hydroxide in the presence of water to form cementitious compounds.
Volcanic Aggregate: Crushed volcanic rocks (ash, pumice, scoria) used as inert filler or reactive pozzolanic material in construction composites.
Impermeability: The quality of not allowing fluids (like water) to pass through.