Comprehensive Guide to Mechanical Work and Inorganic Chemical Nomenclature

Mechanical Work Principles and Calculations

• Fundamental Definition of Mechanical Work

  • Mechanical work occurs when an external force is applied to an object and causes a displacement of that object in the direction of the applied force.

  • Mathematical formula for mechanical work:     $W = F \times d$

• Variables, Definitions, and Units

  • Symbol $W$: Represents mechanical work (Trabajo mecánico).

  • Unit: Joules ($J$), where $1\,J = 1\,N \cdot m$

  • Symbol $F$: Represents applied force (Fuerza).

  • Unit: Newtons ($N$)

  • Symbol $d$: Represents displacement or distance (Distancia / Desplazamiento).

  • Unit: Meters ($m$)

• Worked Example Problem

  • Problem Scenario: A person applies a force to move a box across a flat surface over a distance of $4\,m$. Calculate the total mechanical work performed.

  • Given Data:

  • Applied force: $F = 50\,N$

  • Distance / Displacement: $d = 4\,m$

  • Formula: $W = F \times d$

  • Substitution: $W = 50\,N \times 4\,m$

  • Calculation / Operation: $50 \times 4 = 200$

  • Final Answer: $W = 200\,J$

• Conceptual Analysis: Existence of Mechanical Work

  • Scenario 1: Carrying a backpack while walking horizontally

  • Is work performed?: No

  • Explanation: The vertical lifting force applied to hold the backpack is perpendicular ($90^\circ$) to the horizontal displacement. Because there is no force component acting in the direction of motion, no mechanical work is done on the backpack in the direction of movement.

  • Scenario 2: A person pushing a box

  • Is work performed?: Yes

  • Explanation: An applied force acts directly on the box, causing it to undergo displacement in the line of action of the force.

  • Scenario 3: A moving cart being pushed forward

  • Is work performed?: Yes

  • Explanation: The applied force acts on the cart and causes it to displace across a measurable distance in the direction of the force.

Chemical Nomenclature: Writing Compound Names from Chemical Formulas

• Metallic Oxides (Óxidos Metálicos)

  • Chemical formula $Fe_2O_3$: Iron (III) oxide (Óxido de hierro (III))

  • Chemical formula $CuO$: Copper (II) oxide (Óxido de cobre (II))

  • Chemical formula $MgO$: Magnesium oxide (Óxido de magnesio)

  • Chemical formula $SrO$: Strontium oxide (Óxido de estroncio)

  • Chemical formula $PbO$: Lead (II) oxide (Óxido de plomo (II))

• Non-Metallic Oxides (Óxidos No Metálicos / Anhydrides)

  • Chemical formula $CO_2$: Carbon dioxide (Dióxido de carbono)

  • Chemical formula $N_2O_5$: Dinitrogen pentoxide (Pentóxido de dinitrógeno)

  • Chemical formula $SO_3$: Sulfur trioxide (Trióxido de azufre)

  • Chemical formula $Cl_2O_7$: Dichlorine heptoxide (Heptóxido de dicloro)

  • Chemical formula $P_2O_5$: Diphosphorus pentoxide (Pentóxido de difósforo)

• Hydrides (Hidruros)

  • Chemical formula $LiH$: Lithium hydride (Hidruro de litio)

  • Chemical formula $FeH_3$: Iron (III) hydride (Hidruro de hierro (III))

  • Chemical formula $CaH_2$: Calcium hydride (Hidruro de calcio)

  • Chemical formula $SnH_4$: Tin (IV) hydride (Hidruro de estaño (IV))

  • Chemical formula $CuH_2$: Copper (II) hydride (Hidruro de cobre (II))

• Hydracids / Binary Acids (Hidrácidos)

  • Chemical formula $HCl(aq)$: Hydrochloric acid (Ácido clorhídrico)

  • Chemical formula $HF$: Hydrogen fluoride (Fluoruro de hidrógeno)

  • Chemical formula $H_2S(aq)$: Hydrosulfuric acid (Ácido sulfhídrico)

  • Chemical formula $HI$: Hydrogen iodide (Yoduro de hidrógeno)

  • Chemical formula $H_2Se(aq)$: Hydroselenic acid (Ácido selenhídrico)

• Binary Salts (Sales Binarias)

  • Chemical formula $NaCl$: Sodium chloride (Cloruro de sodio)

  • Chemical formula $ZnS$: Zinc sulfide (Sulfuro de zinc)

  • Chemical formula $AuBr_3$: Gold (III) bromide (Bromuro de oro (III))

  • Chemical formula $MgF_2$: Magnesium fluoride (Fluoruro de magnesio)

  • Chemical formula $FeCl_2$: Iron (II) chloride (Cloruro de hierro (II))

• Binary Compounds Between Non-Metals (Compuestos Binarios entre No Metales)

  • Chemical formula $CF_4$: Carbon tetrafluoride (Tetrafluoruro de carbono)

  • Chemical formula $PCl_3$: Phosphorus trichloride (Tricloruro de fósforo)

  • Chemical formula $SF_6$: Sulfur hexafluoride (Hexafluoruro de azufre)

  • Chemical formula $ICl$: Iodine monochloride (Monocloruro de yodo)

  • Chemical formula $As_2S_3$: Diarsenic trisulfide (Trisulfuro de diarsénico)

Chemical Nomenclature: Writing Chemical Formulas from Compound Names

• Metallic Oxides

  • Calcium oxide: $CaO$

  • Iron (III) oxide: $Fe_2O_3$

  • Copper (II) oxide: $CuO$

• Non-Metallic Oxides

  • Carbon dioxide: $CO_2$

  • Diphosphorus pentoxide: $P_2O_5$

  • Sulfur trioxide: $SO_3$

• Hydrides

  • Lithium hydride: $LiH$

  • Calcium hydride: $CaH_2$

  • Iron (III) hydride: $FeH_3$

• Hydracids / Binary Acids

  • Hydrochloric acid: $HCl(aq)$

  • Hydrogen fluoride: $HF$

  • Hydrosulfuric acid: $H_2S(aq)$

• Binary Salts

  • Sodium chloride: $NaCl$

  • Zinc sulfide: $ZnS$

  • Gold (III) bromide: $AuBr_3$

• Binary Compounds Between Non-Metals

  • Carbon tetrafluoride: $CF_4$

  • Phosphorus trichloride: $PCl_3$

  • Sulfur hexafluoride: $SF_6$