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One atom of an element contains 12 electrons, 12 protons and 13 neutrons. What is the nucleon number of this atom?

13 hours ago | [YT] | 0

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Four statements about the arrangement or movement of particles are given. Which statements describe the particles in a pure solid?

1) Particles are packed in a regular arrangement.
2) Particles are randomly arranged.
3) Particles move over each other.
4) Particles vibrate about fixed points.

1 day ago | [YT] | 2

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Which statement about paper chromatography is correct?

2 days ago | [YT] | 2

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What is used to test for chlorine?

3 days ago | [YT] | 4

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Ethanol is manufactured by two different processes. Which raw materials are used by the two processes to make ethanol?

4 days ago | [YT] | 1

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A small quantity of a solid is added to a large excess of aqueous ethanoic acid. No bubbles of gas are seen and the solid dissolves to give a colourless solution. What is the solid?

5 days ago | [YT] | 4

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Which gas is the main constituent of natural gas?

6 days ago | [YT] | 1

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Which statements about alkenes are correct?

1) Propene is a saturated hydrocarbon.
2) Ethene is made by heating long-chain alkanes to a high temperature in the presence of a catalyst.
3) Hexene reacts with aqueous bromine, changing its colour from colourless to orange.
4) Ethene, propene and butene have the same general formula.

1 week ago | [YT] | 5

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Which statement about the composition of clean, dry air is correct?

1 week ago | [YT] | 1

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What is the colour change when water is added to anhydrous copper(II) sulfate?

1 week ago | [YT] | 2