Q31. What is the chemical symbol for sodium?
Correct: Na
Sodium is represented by Na.
Q32. Which acid is used in car batteries?
Correct: Sulfuric acid
Lead-acid batteries use sulfuric acid.
Q33. What is dry ice?
Correct: Solid carbon dioxide
Dry ice is solid CO2.
Q34. Which element has symbol K?
Correct: Potassium
K is the symbol for potassium.
Q35. What is the formula of sulfuric acid?
Correct: H2SO4
Sulfuric acid has the formula H2SO4.
Q36. Which gas is used in photosynthesis?
Correct: Carbon dioxide
Plants use CO2 to make food.
Q37. What is the chemical name of chalk?
Correct: Calcium carbonate
Chalk is calcium carbonate.
Q38. Which metal is the best conductor of electricity?
Correct: Silver
Silver has the highest conductivity.
Q39. What is the symbol of chlorine?
Correct: Cl
Chlorine is represented by Cl.
Q40. Which compound is used to make plaster of Paris?
Correct: Calcium sulfate
Plaster of Paris is made from calcium sulfate.
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