India first took part in the Olympic Games in the year
a) 1920
b) 1928
c) 1972
d) 1974

The foirst Asian Games were held in
a) China
b) India
c) Pakistan
d) Iran

Toda tribes mainly live in
a) Madhya Pradesh
b) Tamil Nadu
c) Kerala
d) Odisha

Which of the following sanctuary is well-known for elephants
a) Kanha
b) Gir
c) Kaziranga
d) periyar

Which of the following is an accurate method to determine the pH of an aqueous solution?
Litmus
Phenolphthalein
Phenol red
pH meter

Classical pH meter in chemical or clinical laboratory is made with a glass electrode that is selectively sensitive to ______ concentration.
 Na⁺
 K⁺
 H⁺
 OH^-

Calibration should be performed with at least _________buffer(s) that span of range of pH to be measured.
 one
 two
 three
 four

pH meter gives an electrical response proportional to the concentration of hydrogen ion. To convert this response into pH, glass electrode must be calibrated against standard solution of known H+ concentration. Which of the following standard solution(s) is/are likely to be used.
 pH 4.0 buffer
 pH 7.0 buffer
 pH 10 buffer
 All of the above.

After each single measurement, the probe is rinsed with ____________ to remove any trace of the solution being measured.
I. Ionized water
II. Distilled water
III. Deionized water

 I only.
 I and II only.
 II and III only.
 None of the above.

Permissible limit of alkalinity in drinking water is
a : 50mg/l
b : 300mg/l
c : 20-200mg/l
d : 100mg/l

Alkalinity in waste water is useful because it provides buffering to resist changes in pH value.
a : True
b : False