This question is about potassium and zinc - Edexcel - GCSE Chemistry - Question 5 - 2021 - Paper 1
Question 5
This question is about potassium and zinc.
(a) Which of the following temperatures is most likely to be the melting point of potassium?
A -63°C
B 63°C
C 63... show full transcript
Worked Solution & Example Answer:This question is about potassium and zinc - Edexcel - GCSE Chemistry - Question 5 - 2021 - Paper 1
Step 1
Which of the following temperatures is most likely to be the melting point of potassium?
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Answer
The answer is C -63°C as this is the only logical option. Potassium has a low melting point compared to many metals, and a melting point of 630°C is too high.
Step 2
Explain how the electronic configuration of an atom of potassium is related to its position in the periodic table.
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Answer
The electronic configuration of potassium is 2.8.8. The number of electrons in the outer shell indicates the group number, which is 1 for potassium, showing it is in Group 1 of the periodic table. Additionally, the number of electron shells shows the period number, which is 4 in this case.
Step 3
Describe the test to show that a gas is oxygen.
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Answer
To show that a gas is oxygen, a glowing splint can be used. When a glowing splint is placed in a test tube containing the gas, it reignites, indicating the presence of oxygen.
Step 4
Write the electronic configurations for the ions in potassium oxide, K₂O.
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