| Elements in Group 7 of the periodic table, including fluorine, chlorine, bromine, iodine, and astatine, collectively known as halogens. | Halogens |
| Where are Group 7 elements located on the periodic table? | Group 7 elements, also known as halogens, are found on the right side of the periodic table. |
| Halogens belong to this category, exhibiting characteristics such as low conductivity and lack of metallic luster. | Non-Metals |
| What is the molecular structure of halogens? | Halogens exist as molecules made of pairs of atoms that are covalently bonded together. An example is Cl2, where two chlorine atoms are covalently bonded. |
| Halogens achieve this by forming molecules through covalent bonding, ensuring both atoms in the molecule have a complete outer electron shell. | Stable Full Outer Shell |
| How many electrons do halogens have in their outer shell? | Halogens have 7 electrons in their outer shell, contributing to their similar chemical reactivity. |
| Due to having 7 electrons in their outer shell, halogens react in similar ways, exhibiting comparable chemical behaviors across the group. | Similar Reactivity of Halogens |
| Why do halogens all react in similar ways? | Halogens have 7 electrons in their outer shell, leading to similar reactivity patterns as they strive to achieve a stable full outer shell through chemical reactions. |
| The observed pattern where the melting and boiling points of halogens increase as you move down Group 7 of the periodic table. | Halogen Melting and Boiling Points Trend |
| What is the state of halogens at the top of Group 7 at room temperature? | Halogens at the top of Group 7 are gases at room temperature. |
| Halogens at the bottom of Group 7 are solids at room temperature. | State of Halogens at the Bottom of Group 7 |
| What factor influences the increase in melting and boiling points of halogens down the group? | The increase in melting and boiling points is influenced by the increasing relative atomic mass of halogens. |
| Larger halogen atoms have stronger intermolecular forces between them, contributing to higher melting and boiling points. | Intermolecular Forces in Larger Atoms |
| Why do larger atoms require more energy to change from a solid to a gas? | Larger atoms have stronger intermolecular forces, requiring more energy (higher temperature) to overcome these forces and transition from a solid to a gas. |
| The correlation between the increasing relative atomic mass of halogens and the corresponding rise in their melting and boiling points down Group 7. | Relationship between Atomic Mass and Melting/Boiling Points |
| How does the trend in melting and boiling points align with halogen size in Group 7? | The trend shows that as you move down Group 7, from smaller to larger halogens, the melting and boiling points increase due to stronger intermolecular forces in larger atoms. |
| Chlorine exists as a pale green gas at room temperature. | Chlorine Characteristics |
| What is the physical state and color of chlorine at room temperature? | Chlorine is a pale green gas at room temperature. |
| Bromine exists as a red-brown liquid at room temperature. | Bromine Characteristics |
| Describe the physical state and colour of bromine at room temperature. | Bromine is a red-brown liquid at room temperature. |
| Iodine is a dark grey solid at room temperature. | Iodine Properties |
| What is the physical state and color of iodine at room temperature? | Iodine is a dark grey solid at room temperature. |
| A specific test to identify the presence of chlorine (Cl2) involves placing damp litmus paper in a test tube of gas. | Chemical Test for Chlorine |
| How do you test for the presence of chlorine, and what is the result? | To test for chlorine (Cl2), place damp litmus paper in the test tube of gas. If chlorine is present, the litmus paper will be bleached white. |
| The observed pattern where the reactivity of halogens decreases as you move down Group 7 of the periodic table. | Halogen Reactivity Trend |
| Which halogen is at the top of Group 7 and is the most reactive? | Fluorine, positioned at the top of Group 7, is the most reactive halogen. |
| Astatine, located near the bottom of Group 7, is a much less reactive halogen. | Reactivity of Astatine |
| What influences the reactivity trend of halogens down the group? | The reactivity of halogens decreases with increasing relative atomic mass. |
| Halogens react by gaining 1 electron to fill their outer shells. | Electron Gain in Halogen Reactivity |
| Why does it become harder for halogens to gain an extra electron down the group? | It becomes harder down the group because the number of electron shells in each atom increases, causing the outer shell to be further away from the positive nucleus. |
| The outer shell's increased distance from the positive nucleus down the halogen group makes it harder to gain an extra electron due to increased shielding. | Outer Shell and Positive Nucleus Relationship |
| How does the outer shell's distance impact the reactivity of halogens? | The outer shell's increased distance makes it more challenging for halogens to gain an extra electron as it becomes more shielded from the pull of the positive nucleus, contributing to the decreasing reactivity trend down the group. |
| Compounds formed by the reaction of halogens with hydrogen, resulting in substances like hydrogen chloride (HCl). | Hydrogen Halides |
| How do halogens react with other non-metals to form compounds? | Halogens react with other non-metals by sharing electrons, creating covalent bonds that allow both atoms to complete their outer shells. |
| A chemical bond formed when atoms share a pair of electrons, as observed in the compounds formed by halogens and other non-metals. | Covalent Bond |
| What kind of structures do compounds formed by halogens and non-metals have? | Compounds formed by halogens and non-metals have simple molecular structures, consisting of just a few atoms joined together by covalent bonds. |
| Hydrogen halides, formed by halogens and hydrogen, are gases at room temperature. | Hydrogen Halides at Room Temperature |
| What happens when hydrogen halides dissolve in water? | Hydrogen halides dissolve in water to create acidic solutions; for example, hydrogen chloride solution is known as hydrochloric acid: HCl(aq). |
| Ionic compounds formed when halogens react with metals, resulting in substances like sodium chloride (NaCl). | Metal Halides |
| What type of compounds do halogens and metals form when they react? | Halogens and metals form ionic compounds known as metal halides when they react. |
| Halogens gain one electron from a metal atom during the reaction to complete their outer shell. | Electron Gain by Halogens |
| What charge does a halogen ion have after gaining an electron? | When a halogen gains an electron, it forms an ion with a charge of –1. |
| The bond formed by the attraction between the negative halogen ion and the positive metal ion, holding them together in an ionic compound. | Ionic Bond |
| Describe the formation of sodium chloride (NaCl) from chlorine and sodium. | In the reaction, chlorine gains an electron to form Cl–, which is attracted to Na+ to create the ionic compound NaCl, known as sodium chloride. |
| Instances of metal halides formed by halogens reacting with metals, including KI (potassium iodide) and FeBr3 (iron(III) bromide). | Examples of Metal Halides |
| A chemical reaction where a more reactive halogen displaces a less reactive halogen from an aqueous solution of its salt. | Displacement Reaction |
| What is required for a halogen displacement reaction to occur? | A more reactive halogen to (be able to) displace a less reactive halogen from an aqueous solution of its salt. |
| A solution in which a salt is dissolved in water, allowing for chemical reactions to take place. | Aqueous Solution |
| Provide an example of a displacement reaction involving chlorine, iodine, potassium AND chlorine, bromine, potassium. | Chlorine can displace iodine from a solution of potassium iodide and can displace bromine from a solution of potassium bromide. |
| Displacement reactions can be recognized by a colour change, indicating the occurrence of the chemical reaction. | Recognition of Displacement Reactions |
| How can you identify a displacement reaction? | Displacement reactions can be identified by observing a colour change during the reaction. |
| Halogens with higher reactivity can displace halogens with lower reactivity in displacement reactions. | Reactive Halogens and Displacement |
| Why can chlorine displace both iodine and bromine in displacement reactions? | Chlorine is more reactive than both iodine and bromine, allowing it to displace them in displacement reactions. |
| Displacement reactions involve a transfer of electrons and are categorized as redox (oxidation-reduction) reactions. | Displacement Reactions as Redox Reactions |
| What is the key characteristic of displacement reactions that makes them redox reactions? | Displacement reactions involve a transfer of electrons, making them redox reactions. |
| In the reaction between chlorine and iodide ions, there is a transfer of electrons. | Electron Transfer in Chlorine-Iodide Reaction |
| What happens to iodide ions in the chlorine-iodide reaction? | Each iodide ion (I–) loses an electron, pairing up to form iodine (I2). |
| The principle that oxidation involves the loss of electrons, and reduction involves the gain of electrons, often remembered as OIL RIG. | Oxidation-Reduction (Redox) Reaction Principle |
| How do iodide ions exhibit oxidation in the chlorine-iodide reaction? | Iodide ions (I–) lose electrons in the reaction, undergoing oxidation to form iodine. |
| Chlorine atoms in Cl2 each gain an electron, forming chloride ions (Cl–), in the chlorine-iodide reaction . | Chlorine Reduction to Chloride Ions |
| Why are chlorine atoms considered to be reduced in the reaction? | Chlorine atoms gain electrons in the reaction, leading to their reduction and the formation of chloride ions. |
| In halogen-halide reactions, a more reactive halogen will always oxidize a less reactive halide ion. | Reactivity in Halogen-Halide Reactions |
| How does the reactivity of halogens impact the redox reactions with halide ions? | A more reactive halogen oxidizes a less reactive halide ion in displacement reactions, and halogens become less reactive as you go down Group 7. |
