Heavy Metal Extraction Methods for Waste Analysis
Heavy Metals in Waste: Selective Extraction Methods
Selective extraction is a technique used to separate and analyze metals bound to different components within a waste sample. This method is crucial because the mobility, bioavailability, and environmental impact of heavy metals depend not only on their total concentration but also on how they are bound to the solid phase (Filgueiras et al., 2002). By fractionating metals based on their mobility, selective extraction provides valuable insights into
Read MoreChemistry Fundamentals: Reactions, Equations, and Key Concepts
Metals and Nonmetals
Metals
- Group 1: H, Li, Na, K, Rb, Cs, Fr, Ag
- Group 2: Be, Mg, Ca, Sr, Ba, Ra
- Transition Metals: Cr, Mn, Fe, Co, Ni, Pd, Pt, Cu, Au, Hg
Nonmetals
- Group 13: B
- Group 14: C, Si
- Group 15: N, P, As, Sb
- Group 16: O, S, Se, Te
- Group 17: F, Cl, Br, I
Types of Oxides
- Basic Oxides: Formed by metals, e.g., FeO (Iron Oxide)
- Acidic Oxides (Anhydrides): Formed by nonmetals, e.g., SO2 (Sulfur Dioxide)
Types of Compounds
- Metal Hydrides: Formed by metals and hydrogen, e.g., FeH2 (Iron Hydride)
- Acidic Hydrides:
Periodic Table Properties and Electron Configurations
A repetition of properties occurs when elements are arranged in order of increasing atomic number.
periodic law
type of element characterized by the presence of electrons in the d orbital
transition metal
basis for Mendeleev’s arrangement of the periodic table
atomic mass
subatomic particles that are transferred to form positive and negative ions
electrons
Each period in the periodic table corresponds to a(n)
principal energy level |
The modern periodic table is arranged in order of increasing atomic __
Read MoreComprehensive Chemistry Guide: Properties, Reactions, and Concepts
Chemical Properties
Chemical properties describe the changes that occur during a reaction.
Chemical Changes
Chemical changes involve the formation of new substances when elements or compounds combine.
Physical Changes
Physical changes affect the form or appearance of a substance without altering its chemical composition.
Physical Properties
Physical properties describe the observable characteristics of a substance, such as color, density, and melting point.
Naming Compounds
- Write the name of both elements
Materials: Properties, Types, and Applications
Matter
Paricular elementary (protons, neutrons, electrons) Source
Of materials.
**Natural materials** are obtained directly from nature (from living or inert). Ex: wood, granite, leather, cotton , wool …** Artificial materials** obtained from raw materials (materials extracted from the natural) after a process of recycled materials. are obtained from objects of same material.
Material Properties
A) MECHANICAL:
- Density: d = m / V.
- Hardness: hard material is + another when q is able to scratch the second.
Chemistry Notes: Hydrocarbons, Organic Chemistry, Thermodynamics, and More
Hydrocarbons
Reactions and Concepts
Wurtz Reaction
Alkyl halides react with metallic sodium in dry ether to form alkanes.
Sodium Acetate to Methane and Ethane
Sodium acetate heated with soda lime undergoes decarboxylation to form methane. It undergoes Kolbe’s electrolysis to yield ethane.
Conformations
Different spatial arrangements of atoms due to free rotation around a C-C single bond. Ethane exhibits eclipsed and staggered conformations, with staggered being more stable due to minimized repulsion.
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