Free PDF Chemistry Worksheets To Download or Print

Free PDF Chemistry Worksheets To Download or Print This is a collection of chemistry worksheets in pdf format. The answers to the questions are available on separate worksheets so you can fill them out and then check your work. Please feel free to download these to your computer, print them, and use them as hand-outs. Metals, Nonmetals, and Metalloids WorksheetMetric to English Conversions WorksheetMetric to English Conversions AnswersMetric to Metric Conversions WorksheetMetric to Metric Conversions AnswersTemperature Conversions WorksheetTemperature Conversions AnswersTemperature Conversions Worksheet #2Temperature Conversions Answers #2Moles to Grams Conversions WorksheetMoles to Grams Conversions AnswersFormula or Molar Mass WorksheetFormula or Molar Mass Worksheet AnswersPracticing Balancing Chemical Equations - WorksheetBalancing Chemical Equations - AnswersPracticing Balancing Chemical Equations - Worksheet #2Balancing Chemical Equations - Answers #2Practicing Balancing Chemical Equations - Worksheet #3Balancing Chemical Equations - Answers #3Balancing Equations - Worksheet #4Balancing Equations - Answer Key #4Common Acid Names Formulas - WorksheetAcid Names and Formulas - AnswersPractice Calculations with Moles - WorksheetMole Calculations - AnswersAcid Base pH - WorksheetAcid Base pH - Answers Gas LawsGas Laws AnswersGas Laws Answers - Shown WorkLimiting Reagent - WorksheetLimiting Reagent - AnswersCalculating Molarity - WorksheetCalculating Molarity - AnswersBalancing Redox Reactions - WorksheetBalancing Redox Reactions - AnswersPrintable Element CrosswordPrintable Element Crossword - AnswersChemical Names to Chemical Formulas - WorksheetChemical Names to Chemical Formulas - Answer KeyChemical Formulas to Chemical Names - WorksheetChemical Formulas to Chemical Names - Answer Key Printable Periodic Tables Here are some printable periodic tables to help you out, also in pdf format. Color Printable Periodic Table - Pretty much everything you need that can fit on a page and still be readable. Color table with atomic numbers, element symbols, element names, atomic weights, periods, and groups. [2013 Edition] [2012 Edition]Black/white Printable Periodic Table - Black/white table with atomic numbers, element symbols, element names, atomic weights, periods. [2013 Edition] [2012 Edition]Blank Printable Periodic Table - Fill in the boxes yourself.Electron Configuration Periodic Table - Periodic table that lists the electron configurations for each element.Color Printable Periodic Table - Color table with atomic numbers, element symbols, atomic weights, periods, and groups. (no names)Basic Printable Periodic Table - Black/white table with atomic numbers, element symbols, atomic weights, periods. (no names)Basic Periodic Table with Element Names - Black/white table with element symbols, names, atomic numbers, and periods. (no weights)Basic Periodic Table with Element Nam es (color) - Color periodic table with element symbols, names, atomic numbers, periods, and groups. (no weights) The atomic weights given on these tables are the most recent (2007) values as accepted by the IUPAC. Printable Scientific Method Flow Chart This is a flow chart of the steps of the scientific method, available as a PDF file: Scientific Method PDF Also available is a PDF of a pie chart of the elemental composition of the human body.

Conjugation of Past or Preterite Tense Verbs in Spanish

Conjugation of Past or Preterite Tense Verbs in Spanish As one of Spanishs two simple past tenses, the preterite  has a conjugation that is essential to learn. It is the verb form used most often to tell of events that have already happened and that are seen as completed. The other simple past tense, the imperfect, is used for past actions that are not completed, meaning the past action did not have a definite beginning or a definite end. How to Conjugate the Preterite Tense In Spanish, verbs are the words that change the most often and depend on different tenses, moods, gender, and agreement in person according to what needs to be conveyed in the sentence. A verb ending can indicate when the action occurs, and also give the listener a better idea of who or what is performing the action. As is the case with standard Spanish conjugation rules, the preterite verb forms are made by removing the infinitive ending of the verb, such as -ar, -er or -ir, and replacing it with an ending that indicates who is performing the action of the verb. Verbs agree in person and number. For example, the infinitive or base form of the verb that means to speak is hablar. Its infinitive ending is -ar, and the verb stem is habl-. To say I spoke, remove the -ar, add -à © to the stem, forming hablà ©. Yo hablà © is I spoke. To say you spoke, singular you in an informal way, remove the -ar, add -aste to the stem, forming hablaste:  Tu hablaste is You spoke. Other forms exist for other personal pronouns. The endings are slightly different for verbs that end in -er and -ir, but the principle is the same. Remove the infinitive ending, then add the appropriate ending to the remaining stem. Conjugation of Regular -AR Verbs in the Preterite Tense Person -Ar Ending Infinitive: Hablar Translation: To Speak yo - habl I spoke t -aste hablaste you (informal) spoke l, ella, usted - habl he/she spoke, you (formal) spoke nosotros, nosotras -amos hablamos we spoke vosotros, vosotras -asteis hablasteis you spoke (informal) ellos, ellas, ustedes -aron hablaron they spoke, you (formal) spoke Conjugation of Regular -ER Verbs in the Preterite Tense Person -Er Ending Infinitive: Aprender Translation: To Learn yo - aprend I learned t -iste aprendiste you (informal) learned l, ella, usted -i aprendi he/she learned, you (formal) learned nosotros, nosotras -imos aprendimos we learned vosotros, vosotras -isteis aprendisteis you learned (informal) ellos, ellas, ustedes -ieron aprendieron they learned, you (formal) learned Conjugation of Regular -IR Verbs in the Preterite Tense Person -Ir Ending Infinitive: Escribir Translation: To Write yo - escrib I wrote t -iste escribiste you (informal) wrote l, ella, usted -i escribi he/she wrote, you (formal) wrote nosotros, nosotras -imos escribimos we wrote vosotros, vosotras -isteis escribisteis you wrote (informal) ellos, ellas, ustedes -ieron escribieron they wrote, you (formal) wrote In the preterite tense, regular -er and -ir verbs use the same pattern of endings. Additionally, the first-person plural, the we form of nosotros and nosotras, has the same conjugation for both the present indicative tense and the preterite past tense for -ar and -ir verbs. The word hablamos can mean either we speak or we spoke, and escribimos can mean either we write or we wrote. In most cases, the context of the sentence makes clear which tense is intended. Conjugations of Common Irregular Verbs Below are the preterite-tense for the irregular verbs you are most likely to use. Irregular forms are shown in boldface; the forms given follow the same order as in the charts above, beginning with the first-person singular and continuing to the third-person plural. dar (to give): di, diste, dio, dimos, disteis, dieron. decir (to say, to tell): dije, dijiste, dijo, dijimos, dijisteis, dijeron. estar (to be): estuve, estuviste, estuvo, estuvimos, estuvisteis, estuvieron. haber (to have as an auxiliary verb): hube, hubiste, hubo, hubimos, hubisteis, hubieron. hacer (to make, to do): hice, hiciste, hizo, hizimos, hicisteis, hicieron. ir (to be): fui, fuiste, fue, fuimos, fuisteis, fueron. (Note that the preterite conjugations of ir and ser are identical.) llegar (to arrive): lleguà ©, llegaste, llegà ³, llegamos, llegasteis, llegaron. poder (to be able, can): pude, pudiste, pudo, pudimos, pudisteis, pudieron. poner (to put): puse, pusiste, puso, pusimos, puisisteis, pusieron. querer (to be): quise, quisiste, quiso, quisimos, quisisteis, quisieron. saber (to know): supe, supiste, supo, supimos, supisteis, supieron. ser (to be): fui, fuiste, fue, fuimos, fuisteis, fueron. tener (to have or possess): tuve, tuviste, tuvo, tuvimos, tuvisteis, tuvieron. ver (to see): vi, viste, vio, vimos, visteis, vieron.