Question 3 :
An element A reacts with water to form a compound B which is used in white washing. The compound B on heating forms an oxide C which on treatment with water gives back B. Identify B

Question 4 :
Galvanisation is a method of protecting iron from rusting by coating with a thin layer of

Question 5 :
State True or False : NaCl is not a conductor of electricity in solid state whereas it does conduct electricity in aqueous solution as well as in molten state

Question 7 :
State True or False: Green plants get their food from organic compounds

Question 8 :
A convex lens of focal length 20 cm can produce a magnified virtual as well as real image. Where shall the object be placed for obtaining REAL image?

Question 9 :
<img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b19cea273b230584979b69.PNG' /> <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61cc185278c526e972caea24.PNG' /> In the above images, the first image is the ray of light incident on a concave mirror and the second image is the complete path of the ray. Is the second image correct depiction of the path?

Question 10 :
State TRUE or FALSE : A light ray incident on a rectangular glass slab immersed in any medium emerges parallel to itself.

Question 12 :
The lining becomes thick and spongy which would be required for nourishing the _________ if fertilisation had taken place.

Question 13 :
State true or false: The real image formed by a concave mirror is larger than the actual object when source is at a distance equal to radius of curvature of the concave mirror.

Question 14 :
<img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b19d14273b230584979b98.png' /> In the above given reaction, alkaline $KMnO_4$ acts as

Question 17 :
What would be the position of image formed by convex lens when the object is placed between focus $F_{1}$ and optical centre O ?

Question 18 :
The induced current is found to be the highest when the direction of motion of the coil is at ____ to the magnetic field.

Question 19 :
The magnetic field inside the body forms the basis of obtaining the images of different body parts. This is done using a technique called ____.

Question 20 :
Overloading can occur when the ____ wire and the ____ wire come into direct contact.

Question 24 :
State true or false: Metals lying above hydrogen in activity series can displace hydrogen from dilute acids.