Question
How is charcoal prepared? Explain why, charcoal is a better fuel than wood.

Answer

Charcoal is prepared by burning wood in a limited supply of air, so that water and other volatile materials present in it get removed. Charcoal is a better fuel than wood because it has a higher calorific value than wood, and it burns without producing smoke wheras wood produces a lot of smoke on burning.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

What is a rainbow? Draw a labelled diagram to show the formation of a rainbow.
State the difference between Fleming’s Left - Hand Rule and Fleming’s Right-Hand Rule. Name the electrical devices where these rules find an important application.
Define evolution.
What is electrical resistivity? In a series electrical circuit comprising a resistor made up of a metallic wire, the ammeter reads 5A. The reading of the ammeter decreases to half when the length of the wire is doubled. Why?
A squirrel is in a scary situation. Its body has to prepare for either fighting or running away. State the immediate changes that take place in its body so that the squirrel is able to either fight or run?
A concave lens of focal length 15cm forms an image 10cm from the lens. How far is the object placed from the lens? Draw the ray-diagram.
Complete the following chemical equations:
  1. $\text{C}_2{\text{H}}_5{\text{OH}}+\text{O}_2\xrightarrow{\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }}$
  2. $\text{C}_2\text{H}_5\text{OH}\xrightarrow[443\text{K}]{\text{ }\text{ }\text{Conc.}\text{H}_2\text{SO}_4\text{ }\text{ }\text{ }\text{ }}$
  3. $\text{CH}_3\text{COOH}+\text{NaHCO}_3\xrightarrow{\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }\text{ }}$
Explain giving one example, how highly reactive metals (which are high up in the reactivity series) are extracted.
Draw the ray diagram in your answer book and show the formation of image of object AB with suitable rays. Mention the position and nature of image.
The radius of curvature of a concave mirror is 50cm. Where should an object be placed in the mirror, so as to form its image at infinity? Justify your answer.