Science Class 8th

371. Refractor telescope uses _____

A) Mirror

B) Light

C) Lens

D) Convex

372. Reflector telescope uses _____

A) Mirror

B) Lens

C) Light

D) Dark

373. The _____ collect the radio signals from space and focuses them on the antenna.

A) Dish

B) Mirror

C) Lens

D) None of the above

374. Many changes occur around us all the time. They may be __________.

A)  Physical

B) Chemical

C) Both A and B

D) None of the above

375. Which of the following is an example of chemical reaction:

A) Digestion of Food

B) Process of Respiration

C) Replication of DNA

D) All of the above

376. The reaction can be determined by the following, except which of the following:

A) Change in the color

B) Increase of Mass

C) Release of Gas

D) Emission of light

377. A chemical reaction occurs when two or more simpler substances combine and entire new substances are formed.

A) True

B) False

378. Elements taking part in the chemical reaction are called as:

A) Products

B) Electrolyte

C) Reactants

D) Catalysts

379. The compound that is formed by the reaction is called as:

A) Product

B) Reactants

C) Result

D) Catalyst