26. 10 grams of potassium dichromate are heated with hydrogen chloride, what volume of chlorine at 30° C. and 740 m.m. is given off?

K ̧Cr ̧0, + 14HCl = 7H ̧O + 2KCl + Cr ̧Cl ̧ + 3Cl ̧.

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27. 463 grams of common salt are heated with hydrogen sulphate, what volume of hydrogen chloride is given off?

2NaCl + H2SO1 = Na2SO, + 2HCI.

28. What volume of chlorine will diffuse under the same circumstances as 10 litres of nitrogen?

29. What volume of chlorine at 20° C. is required to convert 10 grams of copper leaf into cupric chloride?

Cu + Cl2 = CuCl2.

30. 5 grams of silver chloride are heated in hydrogen, what volume of hydrogen chloride is formed?

31.

AgCl + H = Ag + HCl.

From 2078 grams of sodium chloride what volume of chlorine can be obtained?

2NaCl + MnO, + 2H,SO1 = 2H2O + Na2SO + MnSO ̧ + CI ̧.

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32. One gram of silver oxide is thrown into hydrogen hypochlorite, what volume of oxygen at 21o C. and 770 m.m. is given off?

Ag2O+ 2HCIO = 2AgCl + H2O +02

33. 8.5 c.c. of the strongest solution of hydrogen chloride (containing 500 times its volume of the normal gas) is warmed with twice its volume of hydrogen sulphate. What volume of hydrogen chloride at 20° C. and 780 m.m. is given off?

34. A solution of 10 grams of bleaching powder is run into excess of hot hydrogen chloride, what volume of chlorine at 13° C. is given off?

CaOCl2+ 2HCl = CaCl ̧ + H ̧O + Cl ̧.

35. A gram of bleaching powder when boiled with cupric oxide gave 80 c.c. of oxygen at 7° C. and 800 m.m. Find the percentage of real bleaching powder in the sample. CaOCI, CaCl, +0.

36.

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When 1.205 grams of bleaching powder were boiled with cupric oxide, 58.5 c.c.

over water were obtained.

of oxygen at 13.5° C. measured

The height of the water column

was 340 m.m. and of the barometer 766 m.m. Find the percentage of real bleaching powder in the sample. CaOCI1 = CaCl, + 0.

37. 50 c.c. of chloroform (A1·5) are run into a hot mixture of potassium dichromate and hydrogen sulphate; what volume of carbonyl chloride at 10°C. and 730 m.m. is evolved?

2CHC1, +30= H2O + Cl2+ 2COCI..

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38. 10 litres of chlorine at 15° C. are passed into a warm mixture of carbon disulphide and antimony pentachloride, how much carbon tetrachloride is formed?

CHAPTER XII.

BROMINE. Br= 80,

1. SEA-WATER contains 0.007 per cent. of magnesium bromide (MgBr,). What volume of it is required to obtain one litre of bromine (A3)?

2. What is the volume of 1000 grams of bromine ▲3? 3. Find the mass of 1 c.c. of bromine vapour (Br2).

4. If the mercury (A13·5) barometer stands at 80 c.m.; how high will one of bromine (A3) stand?

5. Find the percentage composition of bromine hydrate (Br,10H2O).

6. How much potassium bromide is required to prepare 10 grams of bromine ?

2KBr+ MnO2+ 2H2SO̟ ̧ = 2H ̧O + K2SO̟ ̧ + MnSO̟ + Br ̧.

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7. How many grams of bromine are there in a litre of gaseous hydrogen bromide (HBr)?

8. How much potassium (a) bromide, (B) bromate is formed on adding 520 grams of bromine to a solution of potassium hydrate?

6Br+6HKO = 3H2O + 5KBr + KBr0 ̧·

9. Find the mass of 127 c.c. of gaseous hydrogen bromide (HBr)..

10. 9 grams of potassium bromide are distilled with hydrogen phosphate, what volume of gaseous hydrogen bromide at 26° C. is evolved?

KBr+ H2PO1 = KH„PO̟ + HBr.

11. 70 grams of bromine are dissolved in water, what volume of hydrogen sulphide at 15° C. is required to convert them into hydrogen bromide?

12. The strongest solution of hydrogen bromide (HBr A1.515) contains half its mass of real acid, how much bromine is there in a litre of the solution?

13. Find the percentage composition of silver bromide (AgBr).

14. 10 grams of potassium bromate are heated, what volume of oxygen at 13° C is given off?

KBrO2 = KBr+ 30.

15. Hydrogen bromide is 2.71 times as heavy as air, find its molecular weight.

16. 100 grams of water dissolve 3 grams of bromine, if the vapour of the solution be passed through a red-hot tube, what volume of oxygen at 13o C. is set free?

Br2+ H2O = 2HBr + 0.

17. Find the mass of 1 c.c. of bromine (Br) vapour measured at 150° C.

18. 10 grams of phosphorus tribromide are decomposed by water and silver nitrate is added, how much silver bromide precipitates?

PBr2+ 3H ̧0+ 3AgNO ̧ = H,PO + 3HNO, + 3AgBr.

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19. How much phosphorus, and what volume of bromine (43) are required to make 10 litres of hydrogen bromide?

P+ 3Br + 3H20 = H ̧PO ̧ + 3HBr.

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20. De Marignac found that 3-946 grams of silver dissolved in hydrogen nitrate were precipitated by 4.353 grams of potassium bromide. Calculate the atomic weight of bromine.

AgNO2+KBr = KNO2+AgBr.

21. A spherical glass bulb is to contain 10 grams of bromine (▲ 3), what must its internal radius be?