Topic 5 - Compounds Flashcards Preview

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Flashcards in Topic 5 - Compounds Deck (6)
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1
Q

Define compound

A

A substance containing two or more different types of atoms that are chemically bonded together

2
Q

What is the equation for the thermal decomposition of CaCO3

A

CaCO3 ->* CaO + CO2

  • heat to be written above arrow
3
Q

Describe the test for CO2

A

Bubble through limewater, turns cloudy

4
Q

Explain the uses of CO2?

A
  • fire extinguishers (because CO2 is more dense than air)

* carbonated drinks (because CO2 is soluble in water, forming carbonic acid)

5
Q

What is the problem with CO2?

A

It is a greenhouse gas, meaning that it prevents infrared radiation from escaping the earth, heating up the atmosphere and causing global warming

6
Q

Describe the decomposition of copper(II) carbonate

A

CuCO3(s) -> CuO(s) + CO2(g)

  • copper carbonate is a green powder
  • copper oxide is black powder

Heat the copper(II) oxide in a horizontal test tube with a bung with a hole in the centre of it filled by a delivery tube into an empty test tube. Because CO2, it collects at the bottom, and can be collected and tested