today was latinetc, and i had got a fun science all lined up! we were going to make oxygen – woohoo! and test for it. This completes a creating and testing for 3 gases – CO2, O2, H2 – series [yes, should really go for nitrogen, but it is trickier...] We’ll do it again no doubt in the future, but i emphasised the 3 and their tests today, and talked a fair bit about catalysts, being things that can make reactions go faster. We had hydrogen peroxide – which you can buy from a chemist cheaper than ebay [thankyou for t-bird for this nugget, only after i had purchased from ebay!] which will over time produce oxygen all by itself, faster if heated. But a catalyst will speed things up and make v much more ‘interesting’ . We had as our catalyst manganese dioxide – definitely going to be a winner, liver and kiwi fruit. [could use iron oxide but this doesn't do a lot, and lead oxide does do a lot, but i don't have any]. we put 15 mls of h202 with a bit of the catalyst [less than 1/4 tsp of the manganese dioxide] and a squirt of washing up liquid and some food colouring. it foams! we rated our catalysts in order of manganese oxide > liver > kiwi
The reaction is :
2H2O2(aq) -> 2H2O(l) + O2(g)
This is catalysed by a variety of transititional metal compounds and peroxidase enzymes found in many living things.
i also did an adapted genie in a bottle [as had less h202!] that i had practiced at home, so knew to be way safer!! still pretty dramatic, and we got to test for oxygen with glowing spills v successfully. [ps i had also given them my usual scary safety prep talk, we had safety specs, lab coats and gloves, and the foaming controls this a bit. I think we all enjoyed it [mind you, i did have to remind a most of the older group that safety specs are not so good if on the forehead rather than over the eyes ]
K did latin and french, Z did crafts – halloween and firework pics using oil pastels with a watercolour wash, and Merry did pasta and mastered K’s ecokettle! We are going to do the real science for kids next time, with all the children reading or having read to, chapter 1 of whichever level their parent thinks is ok, and then i am going to work out how we can model atoms in the interim, so we can each make one, and do some discussion around the periodic table and atomic weights as we do it.
SO after a bit of planning of groups, which K will tinker with and show and tinker with G, who wasn’t here today so needs to have an input, Merry went home, K did french and then we grown ups chatted as the children did a bit more craft. then we went geocaching for the elusive ones! and this time – fanfare – Z found it! still not quite where we thought it was going to be. SB led a group of children out of view, and BB got hurt, so was a bit cross with her for breaking cardinal rule of going somewhere that i didn’t know about out of eyesight and nearly earshot as well. . We then persuaded kfish to come to the next cache too, which i think she may have regretted… i had the coords only on iphone, which with classic timing ran out of charge when we most needed it [actually ] so Z rang chris and got coords, i had the gps which i don’t know how to use, and in the end kept marking waypoints and deleting them until they were more or less the coords. it was getting dark and looking a bit hopeless, so we gave up, but K and I spotted an interesting log arrangement, J investigated it, and tada!! a geotat cache! BB way too tired so i had a less than nice moment when little A – bless her – passed on what she had chosen mind you, we had had A in our car as she had had a moment too that she never got to go in other peoples cars. SHe and BB had a fab conversation which didn’t make 100% sense from the front… Though that was better than BB and L when i had those 2, who were on the cheeky end of the spectrum [not dreadfully, more mock outrage rather than actual required!!]
got home to find chris had tidied the front room and wrestled with putting the curtains up. oh i DO like a room with curtains!! we had chips, falling asleep half way through, and the rest of us watching a fab programme about optical illusions. now i plan to watch the apprentice on iplayer.
And yes, it is 2 months since my sister died, and have thought about her on and off all day.