MDCAT Chemistry MCQ #379

MDCAT Chemistry MCQ #379

1. Question 1

   Q1. A laboratory technician uses a commercial solution called Formalin to preserve biological specimens. What is the standard percentage composition of this solution?

   • A) 40% Formaldehyde, 50% Water, 10% Ethyl alcohol
   • B) 40% Formaldehyde, 52% Water, 8% Methyl alcohol
   • C) 10% Formaldehyde, 80% Water, 10% Methyl alcohol
   • D) 60% Formaldehyde, 30% Water, 10% Methyl alcohol

   Answer: 40% Formaldehyde, 52% Water, 8% Methyl alcohol

   Explanation: Formalin is a 40% solution of formaldehyde in water. Option C fails because 10% is too dilute for standard preservation.