MCQs and tricks for competition exam.

  Chemistry GK in English:- Acids, Bases and Salts   1.Aqueous solution of acid :-  A. Turns blue litmus red.  B. Turns red litmus blue.  Ans: A. Turns blue litmus red.  2. Aqueous solution of alkali :-  A. Turns blue litmus red.  B. Turns red litmus blue.  Ans: B. Turns red litmus blue.  3. Which acid is found in lemon :-  A. lactic acid  B. tartaric acid  C. acetic acid  D.  Citric Acid  Ans: D. Citric Acid  4. Which of the following acid is used to digest our food:-  A. Hydrochloric acid(HCl)  B. Nitric acid( HNO₃)  C. sulfuric acid  D.  lactic acid  Ans: A.  Hydrochloric Acid(HCl)  5. The pH value of an acid is :-  A.  0  B.  less than 0  C.  more than 7   D.  less than 7   Ans: D. Less than 7  6. What is the pH value of alkali :-  A. less than 0   B. 0  C. more than 7  D. les...

    1) Which of the following is the correct expression for the mass number A? (N = number of neutrons, Z = atomic number): - A) A = Z + N B)A = Z - N C)A = Z × N D) A = Z² - N ANSWER= A) A = Z + N Explain:- Check Answer   2) What is the value of 1 atomic mass unit equal to? :- A) (1/12) × mass of oxygen atom B)(1/12) × C¹² mass of the atom C)(1/12) × mass of nitrogen atom D) (1/12) × mass of He⁴ atom ANSWER= B)(1/12) × C¹² mass of the atom Explain:- Check Answer   3) In Einstein's principle E = mc², what is the value of c?:- A) 2 × 10⁸ m/s B)332 m/s C)3 × 10⁸ m/s D) 776 ×10⁴ m/s ANSWER= C)3 × 10⁸ m/s   Explain:- Check Answer   4) How much energy will we get by converting 1U mass into energy?:- A) 1000 MeV B)746 MeV C)540 MeV D) 931 MeV ANSWER=D) 931 MeV Explain:- Check Answer   5) How much energy will we ...