Shred red cabbage ~ (3/4 of a very small head)
Put the cabbage pieces in a small container ~ ( you can use a Pyrex-4-cup measure, a bowl or even a plastic zipper bag)
Cover the cabbage with very hot water. Let it sleep until the water has cooled. (somewhere between lukewarm and room-temperature)
The purple liquid you've made is your indicator.
Pour it into a container and compost the cabbage.
Now look for substances that may be acids or bases.
Liquids are good, like fruits.
You can also use solids around for baking are good too. (such as baking soda, salt, sugar, cream of tartar...)
Get containers for mixing (such as tea cups, because they are small, shallow and white inside)
Pour the indicator into the tea cups and add an acid or base.
Lemon juice, rice wine vinegar, and apple cider vinegar, turn the cabbage-water indicator into a pink.
Orange juice or fresh oranges (same thing) turn the cabbage-water indicator into an orangish-pinkish color.
Baking soda turns the cabbage-water indicator blue.
Milk (non-fat) turns the cabbage-water indicator turn opaque and milky, yet purple.
An egg white (which won't get into the solution immediately until after a lot of stirring) turns the cabbage-water indicator blue.
Hint:
Bases mostly turn the indicator towards blue-ish colors such as purple, light blue, dark blue, opaque blue...
Acids mostly turn the indicator towards pink-ish colours such as orange-ish pink, floral pink...
(You'll have to keep on testing the cabbage-water indicator in after a day or two to see if the indicator quality persists or degrades.
Net overall dissociation:
Na2CO3 ---> 2Na(-) + CO3(2-)
*The ion charge is in parenthesis
Answer:
1. Exothermic.
2. -1598 kJ.
Explanation:
Hello!
1. In this case, according to the reaction, we can infer that 799 kJ of energy are evolved (given off, released) it means that the enthalpy of reaction is negative as the reactants have more energy than the products; which means this is an exothermic reaction.
2. Here, as we know that the enthalpy of reaction is -799 kJ/mol, we can compute the q-value as shown below, considering the reacted 2 moles of solid iron:
Which means that 1598 kJ of energy are evolved when 2 moles of solid iron react.
Best regards!
Answer:
120 g of NaCl in 300 g H20 at 90 C
Explanation:
At x = 90 go vertical to the line for NaCl...then go left to the y-axis to find the solubility in 100 g H20 = 40
we want 300 g H20 so multiply this by 3 to get 120 gm of NaCl in 300 g
