Take about 2 g barium hydroxide in a test tube. Add 1 g of ammonium chloride and mixwith the help of a glass rod. Touch the bottom of the test tube with your palm.

Name the dilute acid that must be present in order to test for sulfate ions with barium chloride.

Place a few pieces of granulated zinc metal in a test tube.n Add 2 mL of sodium hydroxide solution and warm the contentsof the test tube.n Repeat the rest of the steps as in Activity 2.3 and record yourobservations

Take about 10 mL of distilled water (or rain water) and 10 mL ofhard water (from a tubewell or hand-pump) in separate test tubes.n Add a couple of drops of soap solution to both.n Shake the test tubes vigorously for an equal period of time andobserve the amount of foam formed.n In which test tube do you get more foam?n In which test tube do you observe a white curdy precipitate?

An unseeded BOD test is run using 25 ml of waste water mixed with 200 ml of pure water. The value of k at 20℃ is 0.22 day-1. The initial DO of the mixture is 12 mg/l. After 5 days the DO remains fixed at 4 mg/l. The remaining oxygen demand of the waste after 5 days isans.14.6 mg/lit.35.9 mg/lt.68.2 mg/lit29.3 mg/lit.

An unseeded BOD test is run using 25 ml of waste water mixed with 200 ml of pure water. The value of k at 20℃ is 0.22 day-1. The initial DO of the mixture is 12 mg/l. After 5 days the DO remains fixed at 4 mg/l. The remaining oxygen demand of the waste after 5 days isans.68.2 mg/lit35.9 mg/lt.29.3 mg/lit.14.6 mg/lit.