TEA CHEMISTRY
a. Why does tea change colour after adding lemon juice?
1) Because the professor added an indicator before the experiment.
2) The acid from lemon juice adds an electron to the indicator.
3) Tea contains molecules that behave like indicators.
4) The acid breaks bonds in the molecule.
b. Is there any difference between adding milk before tea and tea before milk for the professor?
1) Yes, there is a big difference
2) He doesn't know because he doesn't like tea with milk
3) No, absolutely
c. What is the task of the machine that we can see in the movie?
1) Measuring different sorts of hydrogen atoms in a molecule.
2) Feeling tastes of different teas and comparing them.
3) Checking if there are any hydrogen atoms in molecules.
d. Nowadays the most popular method of decaffeination is:
1) Using dry-cleaning fluid.
2) Using carbon, chlorine and hydrogen.
3) Using highly compressed CO2.
2. Decide if this statements are true (T) or false (F).
a. Tea with lemon and without it absorbs light in the some way despite having a different colour.
b. Hot water extracts more pesticides from tea than cold water.
c. Caffeine doesn't have a big influence on the taste of tea.
3. Complete the sentences:
a. I don't really like black tea, but I'm .......................... green tea.
b. Lemon juice is very .......................... .
c. We'll try .......................... in some lemon.
d. The acid from the lemon juice .......................... to the molecule of an indicator.
e. (...) it causes the bonds of the molecule to switch around and so they .......................... in quite a different way.
f. When you put tea in water, hot water .......................... a number of different chemicals from tea. These are not .......................... (...).
g. They used a machine called Nuclear .......................... .......................... Spectrometer .
h. It's quite easy to get a .......................... of tea and put it in a tube like this.
i. There I've got a real .......................... of green tea.
j. The traditional way of removing caffeine from coffee or tea is by using .......................... .
k. It is a compound of carbon, chlorine or hydrogen, which sometimes can leave quite unpleasant .......................... in the coffee beans or tea leaves.
l. Nowadays the preferred method for removing caffeine (...) is by using highly compressed carbon dioxide, so called .......................... , which can dissolve out caffeine without dissolving very much else.
m. The caffeine that you extract can be sold on to people who make .......................... .