Science Class 8th

421. Reaction between acid and alkalis is called:

A) Addition Reaction

B) Neutralization Reaction

C) Elimination Reaction

D) None of the above

422. Acids are corrosive and can burn skin and dissolve metal.

A) True

B) False

423. Acids react with _____ to give salt and H2 gas.

A) Non Metals

B) Semi Metals

C) Metals

D) None of the above

424. Acids turn blue litmus into ______.

A) Yellow

B) Black

C) Red

D) None of the above

425. Soft drinks contain which type of acid?

A) Citric

B) Acetic

C) Carbonic

D) Lactic

426. Which of the following is bitter in taste?

A) Salts

B) Acids

C) Alkalis

D) None of the above

427. Alkalis react with ______ to give salt and H2 gas.

A) Non Metals

B) Semi Metals

C)  Metals

D) All of the above

428. Salts cannot be dissolved in water.

A) True

B) False

429. pH is the measure of concentration of H released in the solution.

A) True

B) False

430. pOH is the measure of concentration of OH ions.

A) True

B) False

431. Drains Openers are usually:

A) Basic

B) Alkali

C) Can be Both

D) None of the above

432. Acids can be used to remove rust.

A) True

B) False

433. _______ are used in baking soda preparation.

A) Alkali

B) Acids

C) Salts

D) Both A and B

434. Antacid is used for:

A) Neutralization of Sting of Ant

B) Neutralization of Stomach Acidity

C) Cleaning Tough Spots

D) Detoxifying

435. NaCl and other salts can be used for preservation.

A) True

B) False

436. Which of the following is used top check chemical nature?

A) Taste Test

B) Skin Corrosion  test

C) Indicators

D) None of the above

437. What is the final colour of Methyl Orange in Acid:

A) Red

B) Blue

C) Pink

D) Colorless

438. When an acid combines with an alkali the product formed are:

A) Salts and H2O

B) Salts and C02

C) Salts and H2

D) Alkali and Salts

439. Vinegar is:

A) Acid

B) Alkali

C) Salt

D) None of the above

440. CO2 is produced when an acid reacts with:

A) Carbonates

B) Sulphates

C) Salts

D) Non Metals