FLUORINE
a. What is the name of the professor, who is the one of the countries specialists in fluorine chemistry?
b. Which elements doesn't fluorine react with?
c. When can you see the colour of fluorine properly? What colour is it?
d. Why can't you use glass vessels with fluorine?
e. Why the equipment made of nickel is appropriate?
f. Why does fluorine make such strong bonds?
g. Which groups does apatite contain?
h. What happens if you brush your teeth with fluorides?
2. Fill the gaps using the following words:
|
reactive |
enamel | sodium chloride | rusted | pale green |
| rusty | glass vessels | cool | cold | charcoal |
| bright red | scouring pad | sulphur tetrafluoride | -196oC |
a. The reason that people know about fluorine is that it is one of the really .......................... elements.
b. Platinum hexafluoride is .......................... as it's a gas.
c. Ok, so now I'm going to ........................ this down with liquid nitrogen to .........................
d. I'm really surprised, I thought it would be .......................... and it's dark yellow.
e. It's metal .........................., iron wool.
f. The iron looks as if it's .......................... but the .......................... color is actually iron fluoride.
g. This is .......................... and cold gas, and the gas just touching it.
h. You can't use it in ..........................
i. You are going to oxidize the sulphur, probably to ...........................
j. Your toothpaste contains fluoride and just in the same way that you can use .........................., table salt which contains chlorine, you can use fluorides.
k. The .......................... of your teeth is a compound of calcium called apatite.