Science Summative Unit 1 Preparation PDF

Science Summative Unit 1 Preparation: How Metal is formed from its natural state: Ore —> Metal —> Article Group 1 & 2 Metals and Non-Metals:- Metals General Properties: Luster Ductile Malleable Hard Conductors of Heat And Electricity They are from the alkaline metals, alk...

Science Summative Unit 1 Preparation: How Metal is formed from its natural state: Ore —> Metal —> Article Group 1 & 2 Metals and Non-Metals:- Metals General Properties: Luster Ductile Malleable Hard Conductors of Heat And Electricity They are from the alkaline metals, alkaline earth metals and transition metals Non-Metals General Properties: They’re brittle Dull Not good conductors of heat and electricity Mostly of Gas Metalloids: Metals that are in the stair step (Boron B, Silicon Is, Germanium Ge, Arsenic As, Antimony Sb, Tellurium Te, Polonium Po) Share properties of metals and non-metals. There are 18 groups and 7 periods Valence electrons are in always located in the outermost shell. Group 1 Metals: Alkali metals Lithium Li, Sodium Na, Potassium K, Rubidium, Rb Caesium Cs, Francium Fr They’re very reactive than all other metals. Increase in atomic radius and reactivity Melting and boiling points decrease as we go down the order. Softness increases down the order First three have low density Shiny surfaces dulls when in contact with oxygen (Oxidation) Silvery colored Alkali Metals have only 1 valence electron Group 2: Alkaline Earth Metals Beryllium Be Magnesium Mg Calcium Ca Strontium St Barium Ba Radium Ra Alkaline Earth metals have 2 valence electrons There are less reactive than group 1 They’re not found pure in nature They have more density than group 1High melting and boiling points compared to group 1 Metal Reactivity: Chemical Changes to an object: When a new product is formed and its chemical properties have changed due to chemical reaction. Physical Changes: When the interior or outside of an object changes but its chemical properties are same. They can change by melting point, density, bent (malleable), and colour. Reactivity of metals are on a list based on how reactive they are and the reactivity can vary. The most reactive will react to anything even with a small amount and the least reactive reacts barely reacts, even with high amounts List from most reactive to least reactive metals: Memorize the list ———————————————————————————————————————————————————————— Metal main properties: As heat conductor As an electrical conductor Lusture (Shiny) Malleable (Able to be bent)  Ductile (Able to be formed into wires ———————————————————————————————————————————————————————— How do metals react: Metal Reactions: Corrosion: When metals react with water, oxygen, and moisture in the air, it forms compounds with metals, causing them to corrode and have wear and tear, making them less durable and reliable. Rusting: Its when iron reacts with water or oxygen and forms iron oxide, which is also rusting. Tarnish: When a thin layer forms at the metal when reacting with oxygen Methods to prevent rusting: Painting: It seals a layer of coating on the iron and paint doesn’t react with water or oxyegn when dried so its protects the iron. Protective Coating: Some paints have anti-corrsoive chemicals that further protect it from rust, water, oxygen, and maintains the moisture found in the air. Electroplating: The metal coating can slow down and prevent corrosion and acts as barrier that will slowly break down overtime, needing ot be replaced but can still prevent moisture or water from reacting with the metal underneath the coating. ———————————————————————————————————————————————————————— Metals reacting with acids: The metals react with acid to form salt and hydrogen Formula to remember: Metal + Acid —> Salt + Hydrogen You can tell that this chemical reaction can form hydrogen gas by seeing if the reaction forms bubbles or makes a squeaky sound. ———————————————————————————————————————————————————————— Metals reacting with water: When a metal reacts with water, metal hydroxide and hydrogen are formed. Metal + Water —> Metal Hydroxide + Hydrogen The more reactive the metal, the more rapid the reaction is. Example: Sodium reacts fast with water ———————————————————————————————————————————————————————— Making Electricity with Metals: Electricity can be produced when two metal strips like copper and iron (Electrodes) are in dipped in a salt like solution like sodium chloride (solution is called electrolyte solution). The electrodes can be attached to wires using croc clips (metal clips), then attached to a volt meter to measure the electricity. Also named as an electrochemical series ———————————————————————————————————————————————————————— Electroplating: Its a process that uses metal to coat on an existing metal which is also a type of reaction. This involves an electric current passing through a solution of electrolytes which allows for a transfer of metal ions.