Answer:_____

Write the formula of relationship between normality (N) and molarity (M) of solution.

Answer:_________________

21. Determine the correspondence between titration system and the best indicator:

	Titration system		Indicator	Answer:   A-____________;   B-____________;   C-____________.
A.     B.     C.	0,1 N hydrochloric acid HCl by 0,1 N Sodium hydroxide NaOH (pHeq=7,00) 0,1 N acetic acid CH3COOH by 0,1 N Sodium hydroxide NaOH (pHeq=8,87) 0,1 N hydrochloric acid HCl by 0,1 N Ammonium hydroxide NH4OH (pHeq=5,73)		Alizarin yellow R (pT=11,3) Thymol Blue (pT=1,7) Phenol red (pT=5,8) Bromophenol blue (pT=4,1) Litmus neutral (pT= 7,1) Thymol blue (pT=8,9) Cresol red (pT=8,2) Phenolphthalein (pT=9,6)

22. Calculate pH of 0,01 N NaH₂PO₄ (pK₁=1,96; pK₂=6,70; pK₃=12,44).

	1,96	Answer: _________________
	5,31
	12,92
	7,92

23. It is necessary for preparation of coarse-crystalline sediment:

	To precipitate of hot concentrated solutions;	Answer:_____________
	To precipitate of cold diluted solutions;
	To precipitate of hot diluted solutions;
	To precipitate of cold concentrated solutions.

24. Calculate pH of buffer solution, contained 0,1 mol NH₃ and 0,01 mol NH₄Cl in 1 L (pK (NH₃)=9,24).

  Solution: _________________________________________________________________________   _________________________________________________________________________________   Answer:_________________

25. Calculate Redox potential of solution, contained 0,01 N КMnO₄ and 0,001 N MnSO₄ per 1 L at рН=3 (E_o = + 1,51 V).

Solution: _________________________________________________________________________   _________________________________________________________________________________   Answer:_________________

26. Calculate dissociation degree α of 0,1 N H₃BO₃ (K _{1 dis}=5,8×10^-10)

Solution:___________________________________________________

Answer:__ α =______

27. Equivalent mass of Ce³⁺ (A=140,12 g/mol) cation in reaction with Trilon B is:

	140,12 g-eq/g;	Answer:_____________
	70,06 g-eq/g;
	46,71 g-eq/g;
	16,75 g-eq/g;
	53,96 g-eq/g.

28. Note functional groups in the formula of Trilon B

_________-	CH2		CH2	- COONa
		N-CH2-CH2-N
NaCOO-	CH2		CH2	- _________

29. Calculate concentration of solution, contained 0,008 g of solute in 1000 g of solution.

	8 ppm;	Answer:_____________
	800 ppm;
	0,8 ppm;
	80 ppm;
	0,008 ppm.

Write formulas of temporary hardness salts – cause of scale formation

Cause of scale?

Answer: Formulas of dissolved salts in fresh water:________________________

Дата добавления: 2015-11-16