Chemistry

Electrochemistry Marking Scheme This is the marking scheme for quiz: C4 - Electrochemistry Quiz Topic Guide: C4 - Electrochemistry Section A: Multiple Choice (5 Marks) D [1] (Anode is positive; oxidation is loss of electrons) C [1] (Bromine gas $\text{Br}_2$ is reddish-brown) B [1] (In aqueous $\text{NaCl}$, $\text{H}^+$ is reduced at cathode instead of $\text{Na}^+$) B [1] (Object to be plated is always the cathode) B [1] (Water is the only product) Section B: Short Answer (15 Marks) Process: ...

Electrochemistry Quiz Duration: 45 Minutes Total Marks: 30 Section A: Multiple Choice (5 Marks) In an electrolytic cell, the electrode where oxidation occurs is the: A. Cathode (negative) B. Cathode (positive) C. Anode (negative) D. Anode (positive) What is the observation at the anode during the electrolysis of molten lead(II) bromide ($\text{PbBr}_2$)? A. Grey metallic deposit B. Colorless bubbles of gas C. Reddish-brown fumes D. Pale green gas Which of the following is correct for the electrolysis of concentrated aqueous sodium chloride ($\text{NaCl}$)? A. Sodium metal forms at the cathode. B. Hydrogen gas forms at the cathode. C. Oxygen gas forms at the anode. D. Chlorine gas forms at the cathode. ...

Stoichiometry Quiz Duration: 45 Minutes Total Marks: 30 Section A: Multiple Choice (5 Marks) What is the relative formula mass ($M_r$) of $\text{Ca(OH)}_2$? ($A_r$: $\text{Ca} = 40, \text{O} = 16, \text{H} = 1$) A. 58 B. 74 C. 82 D. 90 Which of the following represents the correct molar gas volume at r.t.p.? A. 1 mole = $22.4\text{ dm}^3$ B. 1 mole = $24\text{ dm}^3$ C. 1 mole = $24,000\text{ cm}^3$ D. Both B and C ...

Comprehensive guide covering the chemical and physical properties of metals, reactivity, extraction, and corrosion.

Structure and position The Periodic Table arranges elements in order of increasing proton number. Horizontal rows are periods; vertical columns are groups. Elements in the same group have similar chemical properties because they have the same number of outer-shell electrons. Across a period, metallic character generally decreases and non-metallic character increases. Position predicts electronic configuration, ion charge, reactivity, and physical properties. Group I atoms lose one outer electron to form $+1$ ions; Group VII atoms gain one electron to form $-1$ ions, because both processes produce a full outer shell. ...