tests for salts - 6th may

today during lunch, and continuing into period five. and i NEEDED ALL THIS TIME!!

this test was the longest, however i did eventually get my results.
i didn't need much help from ms B, simply because i had already seen Eliza and Sarah doing it and had talked to Eliza about what to do
the only thing i couldn't work out was how to get the filter paper to stay in the funnel
but ms B helped, and i was on my way

What i did for soil was:

• set up 3 retort stands with boss heads and clamps
  
• placed a funnel in each of these clamps
  
• using 3 of the 4 samples taken from the grassy area first, i placed one piece of filter paper, securing it in place with some demineralized water in each funnel, and poured the mixture of each sample (2 spoons of soil and demineralilzed water) into the funnel
  
• i waited for enough of the solution to drain
• and then added, drop by drop, the silver nitrate. this was using my black cardigan as a backdrop so i could observe the colour change more accurately
  
• i repeated this experiment 3 times for each of the 8 samples and got the same results every time
• my experiment was reliable and there was no major variation in results :)

My results:

this is measured in how many drops of silver nitrate i had to add to the solution before i saw some colour change and that the solution had gone cloudy

• for the samples of soil from the park area:
• a) 1 drop (each time)
  
• b) 1 drop (each time)
• c) 1 drop (each time)
• d) 1 drop (each time)

• for the samples of soil from the more moist area near the car park, under the tree:
• a) 1 drop (each time)
• b) 1 drop (each time)
• c) 1 drop (each time)
• d) 1 drop (each time)

What i did for water was:

• set up a test tube rack, with 6 small test tubes
  
• rinsed them out, to avoid contamination
  
• filled each with some of the water sample (purple, green, blue)
• this meant that the test was already being repeat twice, which i then did it another time
• but i added, drop by drop the silver nitrate
• the results once again were all the same :)

My results:

• for the water from the sand spit:
• a) 1 drop (each time - 3)
• for the water from the popular side:
  
• a) 1 drop (each time - 3)
• for the water from the more narrow side:
• a) 1 drop (each time - 3)

some other results i noticed was that with the water, not the soil, after adding the silver nitrate, not only did the water turn cloudy buy small clumps formed and began to sink to the bottom.

some photos:


The set up of the experiment



6 of the cloudy samples after 1 drop




1 of the test tubes. As you can see, sediments are forming where the silver nitrate has been added. and every tube turned out like this.

what i had to remember to do with the solutions i had added silver nitrate to was to put the waste in the waste bucket rose had ordered. this is a requirement as the chemical can be dangerous if not handled with care.

I have developed a scale:

1 - 2 drops = very salty ***
3 - 4 drops = medium salt quantity
5 - 6 drops = little salt content
>6 drops or no reaction = almost no salt