Class 9th · Chemistry · Chapter 9
Chapter 9: Group Properties and Elements
Chapter 9 of the Punjab Board Class 9th Chemistry textbook runs from page 123 to 132. Its exercise has exercise. Open any of those pages in GenZ Books, tap a question, and the answer is worked from this chapter.
Open Chapter 9 of Chemistry in GenZ Books
The same Class 9th textbook, page for page. Tap any question and get the answer worked from that chapter — English and Urdu.
What you will learn
- Define group 1 Alkali metals as relatively soft metals with general trends down the group limited to decreasing melting point, increasing density and increasing reactivity
- Predict properties of other elements in group 1, given information about the elements
- Predict properties of elements in group 1 in order of reactivity given relevant information
- Define group 17 halogens as diatomic non-metals with general trends limited to increasing density, and decreasing reactivity
- Identify the appearance of halogens at rtp as fluorine as pale-yellow gas, chlorine as yellow -green gas, bromine as red -brown liquid, iodine as grey- black solid
- Explain the displacement reactions of halogens with other halide ions and also as reducing agents
- Predict the properties of elements in group 17, given information about the elements
- Analyse the relative thermal stabilities of the hydrogen halides and explain these in terms of bond strengths Transition elements
- Describe the transition elements as metals that: have high densities, high melting points, variable oxidation numbers, form coloured compounds and act as catalysts for industrial purposes
Exercise
- Exercisep. 130