AS 1141.35:2019 pdf free
AS 1141.35:2019 pdf free.Methods for sampling and testing aggregates
Prepare solutions as follows: .
(a) Solution A: Dissolve 17.3 g of CuSO4.5H2O in water, and dilute the solution to.250 mL.
(b) Solution B: Dissolve 30 g of NaOH in water and warm the solution. Dissolve 86.5 g.of Rochelle salt in the warm NaOH solution. Cool the solution and dilute to 250 mL.
(c) Fehling ‘s solution: Mix equal volumes of Solution A and Solution B to make Fehling’s solution. This solution is used for detection of sugar. Fehling’ s solution must be made immediately before use. It is not stable and must not be kept for more than 12 h.
The procedure shall be as follows:
(a) Place a test sample of approximately 100 g of aggregate in a 250 mL beaker and cover it with water. Add 50 mL of 1 M HCl and boil the mixture for 5 min, then filter while still hot.
(b) If the filtrate is acid to litmus paper, cool 5 mL of it, neutralize it with 1 M NaOH solution and remove any precipitate by filtration. Add 3 mL of Fehling’ s solution,thoroughly stir the resultant mixture, and heat it in a boiling water bath for 5 min.
(c) If sugar is present, a reddish-brown precipitate will be formed.
(d) If the original filtrate is not acid to litmus paper, add a further 50 mL of 1 M HCl and boil the mixture for a further 5 min (this should ensure that the filtrate is acid to litmus paper), then continue as in Step (b) for a filtrate that is acid to litmus paper.
NOTE: For this test it is intended that the filtrate be acid to litmus paper. A neutral or alkaline reaction indicates that the HCl has been neutralized by carbonates in the aggregate. This condition must be corrected by adding HCl and boiling the mixture.
Standards are living documents which reflect progress in science, technology and systems. To maintain their currency, all Standards are periodically reviewed, and new editions are published. Between editions, amendments may be issued. Standards may also be withdrawn. It is important that readers assure themselves. they are using a current Standard, which should include any amendments which may have been published since the Standard was purchased.AS 1141.35 pdf free download.
