4.9.4 Properties and Uses of Metals and Non-metals (Structured Questions)

Question 1:Diagram 1.1 and Diagram 1.2 show an experiment to study the heat conductivity between metal and non-metal.Table shows the time taken for the thumb-tack to fall after both rods are heated.(a) State one hypothesis for this experiment. [1 mark](b) State the variables in this experiment.   (i) Constant variable [1 mark]   (ii) Manipulated variable … Read more

4.5.2 Classification of Substances

4.5.2 Classification of Substances 1. Types of substances:   2. The physical properties of substances depend on (a)  types of particles they contain,    (b)  arrangement of the particles,    (c)  forces of attraction between the particles. Substances made of atoms (or Atomic substances) 1.   Atomic substances are substances that consist of only atoms. 2. … Read more

4.5 Properties of Substances Based on their Particle Content

4.5 Properties of Substances Based on their Particle Content 1.   Matter is anything that occupies space and has mass. 2.   Matter can be divided into elements and compounds. 4.5.1 Atoms, Molecules and Ions 1.   Substances are made of tiny particles called atoms, molecules and ions. 2.   Atoms are the tiniest particles in an element. 3.  … Read more

4.4 Classification of Elements in the Period Table

4.4 Classification of Elements in the Period Table 4.4.1 The classification of Elements 1. In modern periodic table, the elements are arranged in ascending order of proton number. Group 1. The vertical columns of the periodic table is called group. 2. There are 18 groups in the periodic table. 3. Elements in the same group have similar chemical properties. … Read more

4.3.2 Isotopes

4.3.2 Isotopes 1. Isotopes are atoms of certain elements which have the same number of protons but different number of neutrons in the nucleus of the atoms. 2. Isotopes of the same element have same chemical properties. For example, both carbon-12 and carbon-13 burn in oxygen to form carbon dioxide.   3. Physical properties of isotopes are different. … Read more