Science Class 8th
401. When _____ is heated at very high temperature CO2 and CaO are formed.
A) Sulpher Oxide
B) Marble
C) Cement
D) Calcium Carbonate
402. During a chemical reaction heat is ______.
A) Absorbed
B) Released
C) Both A and B
D) None of the above
403. Heat evolved or absorbed during a chemical reaction is called the ______.
A) Specific Heat
B) Heat Capacity
C) Heat of Reaction
D) Total Heat
404. There are ____ types of reaction with respect to the energy changes.
A) Two
B) Three
C) Six
D) Seven
405. Chemical reactions in which heat is released.
A) Endothermic
B) Exothermic
C) Both A and B
D) None of the above
406. Chemical reactions in which heat is absorbed.
A) Endothermic
B) Exothermic
C) Both A and B
D) None of the above
407. Which of the following occurs at the SUN:
A) Endothermic Reaction
B) Exothermic Reactions
C) Both A and B
D) None of the above
408. Breakdown of glucose inside the body is an _____ reaction.
A) Endothermic
B) Exothermic
409. Rusting of iron is an example of chemical reaction:
A) True
B) False
410. Symbols is the best way to express a chemical reaction:
A) True
B) False
411. What changes occur in the solution of AgNO3 and NaCl in the presence of sunlight.
A) Gas Evolved
B) Heat is produced
C) Precipitate is formed
D) No Change is observed
412. The total energy of the product in an ______ reaction is less than that of the reactant.
A) Exothermic
B) Endothermic
C) Both A and B
D) Addition
413. When Iron rusts, it reacts with:
A) Carbon
B) Oxygen in the Air
C) Nitrogen in Air
D) Chlorine
414. Common Table Salt:
A) Sodium Chloride
B) Calcium Carbonate
C) Magnesium Carbonate
D) None of the above
415. Which of the following is present in vinegar?
A) Lactic Acid
B) Acetic Acid
C) Hydrochloride Acid
D) Citric Acid
416. There are _____ main types of chemical compounds.
A) Two
B) Three
C) Four
D) Five
417. The _____ taste in fruits is due to acids.
A) Salty
B) Sugary
C) Bitter
D) Sour
418. The word acid is derived from a ______ word.
A) English
B) Roman
C) French
D) Latin
419. Alkalis are sweet in taste and rough in touch.
A) True
B) False
420. Salts are formed by the reaction of acids and alkalis.
A) True
B) False