[chaneliman]

Okay i'm gonna throw it out there. These are the question i can't do. Some of them r probably really easy but my textbook has no explanation

1. The concentration of sodium hyroxide in waste water from an alumina refinery was found by titrating 20ml aliquots of waste water agaisint .15M hydrochloric acid, using phenolphthalein as indciator. The average titre of several titration was 11.4ml. What mass of sodium hydroxide would be present in 100L of the waste water?

2. A 1.20 g anatacid tablet contains 80.% by mass of magnesium hyroxide as the acitve ingredient. What volume of .15M hydrochloric acid could the anatacid tablet neutralise?

3 What volumes of .1M sulfuric acid woould be requires to neutralise a solution containing .5g of sodium hydroxide and .8g of potassum hydroxide?

4. A certain brand of washing soda contains partially hydrated sodium carbonate solid. A .3g sample completely reacts with 20ml of .250M hydrochloric acid. Calculate the percentage by mass of sodium carbonate in the washing soda.

thanks a heapzzzzzzzzzzzzzzzzzzz

[Borek]

Start with reaction equations.