Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Principles of Chemistry
991 practice questions
Topics covered
- States of Matter102 practice questions
- Elements, Compounds and Mixtures69 practice questions
- Atomic Structure108 practice questions
- The Periodic Table103 practice questions
- Chemical Formulae, Equations and Calculations Part 119 practice questions
- Chemical Formulae, Equations and Calculations Part 2144 practice questions
- Ionic Bonding143 practice questions
- Covalent Bonding68 practice questions
- Metallic Bonding19 practice questions
- Electrolysis198 practice questions
Practice questions
581–590 of 991
Question 581
2 marks · Hard
Answer and see the solution →A calcium atom (Ca) forms a Ca ion. Describe what happens to the atom when it forms this ion and explain why it forms an ion with a charge of 2+.
Question 582
5 marks · Hard
Answer and see the solution →Phosphorus is a Group 5 element with atomic number 15.
(a)[1 mark]Describe how a phosphorus atom forms a phosphide ion ().
(b)[1 mark]Write the electronic configuration of a phosphide ion.
(c)[2 marks]Explain why the phosphide ion is isoelectronic with a noble gas atom. Name the noble gas.
(d)[1 mark]State the total number of electrons in a phosphide ion.
Question 583
2 marks · Hard
Answer and see the solution →Explain why a bromide ion () has the same number of electrons as a krypton atom.
Question 584
1 mark · Easy
Answer and see the solution →State the number of electrons transferred from a lithium atom to a fluorine atom when lithium fluoride is formed.
Question 585
3 marks · Easy
Answer and see the solution →(a)[1 mark]State the formula of the calcium ion formed in calcium chloride.
(b)[1 mark]State the formula of the chloride ion formed in calcium chloride.
(c)[1 mark]Draw a dot-and-cross diagram to show the ions in calcium chloride.
Question 586
2 marks · Easy
Answer and see the solution →How many electrons are present in the outer shell of a lithium atom and a fluorine atom before they react to form lithium fluoride? Give your answers as two numbers separated by a comma.
Question 587
2 marks · Easy
Answer and see the solution →Explain why two chlorine atoms are needed to react with one calcium atom to form calcium chloride.
Question 588
3 marks · Easy
Answer and see the solution →Outer shell electrons for Group 1 and Group 7 elements Element Number of outer shell electrons Lithium (Li) 1 Sodium (Na) 1 Fluorine (F) 7 Chlorine (Cl) 7 (a)[1 mark]State the electronic configuration of a lithium atom.
(b)[1 mark]Colour or underline the value in the table that shows how many electrons a fluorine atom has in its outer shell.
(c)[1 mark]Using information from the table, explain why lithium and fluorine are likely to react together to form an ionic compound.
Question 589
1 mark · Easy
Answer and see the solution →Draw a dot-and-cross diagram to represent the chloride ion in calcium chloride.
Question 590
3 marks · Easy
Answer and see the solution →(a)[1 mark]Give the electronic configuration of a fluoride ion (F^-).
(b)[1 mark]Explain how a lithium atom changes to a lithium ion when forming lithium fluoride.
(c)[1 mark]Draw a dot-and-cross diagram for the lithium ion formed.