Have you ever felt overwhelmed while struggling to grasp important O Level concepts like periodicity? If so, know that you’re not alone in encountering this challenge. Many students face difficulties when memorizing the elements and understanding periodic table trends.
One particularly essential yet complex topic in Chemistry is Periodicity, which lays the groundwork for comprehending subsequent concepts. To simplify your exam preparation, we have meticulously curated an extensive six-page cheat sheet exclusively focused on Periodicity.
With our thoughtfully crafted cheat sheet, you’ll confidently navigate the intricacies of Periodicity and tackle challenging exam questions with ease.
P.S. Scroll to the end to download the Pure Chemistry Cheat Sheet
Fundamentals of Periodicity
Periodicity lies at the core of secondary school chemistry education, providing profound insights into the behavior and properties of elements. The periodic table organises elements based on their atomic numbers, which directly corresponds to the number of protons within their nuclei.
While moving leftward within the table, elements actively demonstrate larger atomic sizes; however, progressing downward results in an increase in atomic size. Furthermore, these patterns extend well beyond mere size, encompassing a wide range of properties such as reactivity and chemical bonding.
By delving into these patterns, you actively gain a holistic understanding of the distinct characteristics exhibited by various elements.
Periodicity Qn 1: The effects of water on five metals, A, B, C, D and E, are given in the table. [4 marks]
(a) Place the metals in order of reactivity, starting with the most reactive metal. [1 mark]
Ans: B, E, A, D, C
(b) Which metal could be calcium? [1 mark]
Ans: Metal E.
Explanation: Calcium is part of a group that has a trend of increasing reactivity as you progress down the periodic table. Notably, its relatively slow reaction with cold water closely aligns with the reactivity pattern commonly associated with alkaline earth metals. This alignment strongly indicates that the unknown metal in question is highly likely to be calcium.
(c) Which metal could be silver? [1 mark]
Ans: Metal C.
Explanation: Silver is highly unreactive when exposed to steam, even at elevated temperatures. This characteristic aligns with the silver’s position in the reactivity series of metals.
(d) Why is it not possible for metal E to be copper? [1 mark]
Ans: Copper does not react with water.
Explanation: Copper, situated in the reactivity series of metals, does not react with water. This is primarily because it is a relatively unreactive metal.
Periodic Table: Metals
Metals, spanning a diverse spectrum, actively showcase a wide range of reactivity. Notably, alkali metals and alkaline earth metals particularly stand out as highly reactive elements due to their inherent tendency to readily donate electrons. In contrast, transition metals not only actively display multiple oxidation states but also acts as catalysts in various chemical reactions.
Periodicity Qns 2: Most metal carbonates decompose when heated strongly. [5 marks]
A sample of copper (III) carbonate is heated in a crucible.
(a) What would you observe for this reaction? [1 mark]
Ans: Green solid turns black.
A sample of silver carbonate is heated strongly.
(b) What is observed in this reaction? [1 mark]
Ans: A silvery-grey solid is obtained.
(c) Name the products of the decomposition of silver carbonate. [1 mark]
Ans: Silver metal, carbon dioxide gas and oxygen gas.
(d) Name a metal carbonate that cannot be decomposed by heating. [1 mark]
Ans: Sodium carbonate.
Explanation: Sodium carbonate remains heat stable and cannot be broken down by heating due to the strong ionic bonds between the ions.
Download Link: O Level Periodicity Cheat Sheet
We meticulously craft our O Level Periodicity Cheat Sheet to equip you with highly effective strategies that will facilitate your excellence in exams. Our curriculum, underpinned by extensive research, supports our goal of enhancing your comprehension of the topics assessed within the Chemistry paper. Our pedagogical approach focuses on building a strong foundation, equipping you with the tools needed to triumph in your examinations.
Register for a Science trial class and receive one additional topic on Experimental Chemistry. To sign up for a trial class, simply fill out the Google Form here. With our resources and the guidance of our seasoned educators, you will confidently approach your Chemistry exams, fully equipped and brimming with unwavering confidence.
