University:
Purdue University
Course:
CHM 34201 | Inorganic Chemistry Laboratory
Academic year:

2021
Views:

390

Pages:

2
Author:

folclord7m

Lab 7 Precipitation Reactions Pre-Lab Questions: 1.Underwhatconditionswillaprecipitateform? A precipitate is formed when a solution is formed by mixing a solute and solvent. This causes new combonations of ions to form and if any of the new ions are insoluble in water, it will”fall out as a solid known as a precipitate. 2.Whatinformationdoyouneedtocalculatepercentyield? Percent yield is calculated by (actual yield/theoretical yield)x100. 3.Wherecanyougotofindtheinformationregardingtheatomicmassofanelement? You can find the atomic mass of an element by looking at the periodic table. 4.Whyisatomicmasssignificanttocalculatingpercentyield? The atomic mass helps you find the number of moles in an atom instead of a measurement of mass. Moles are needed to calculate percent yield. Experiment 1: Testing for Calcium Ion, Ca2+ Insert initial image with your name and access code handwritten in the background. Lab 7 Precipitation Reactions Post-Lab Questions: 1.Inyourownwordsdefineanddescribeaprecipitationreaction. A precipitiation reaction is formed when combined solutions create an ion that is insioluble in water, which creates a solid in the solution. 2.Whatisthenameofyourprecipitate? Calcium Flouride 3.WhatisthedifferencebetweenCaandCa2+? Ca is a neutral calcium atom, while Ca 2+ is a positively charged calcium cation. Record your observations here. 1 minute- no precipitate has formed yet; The whole solution is a cloudy white/grey color. 20 minutes- The bottom of the test tube has a white cloudy area where it appears a precipitate will be forming. 35 minutes- The precipitate at the bottom of the test tube is much more solid and forming together. It almost seems as if it is gelatinous when moving the test tube around. 60 minutes- The test tube has a white opaque solid at the bottom. Insert final image with your name and access code handwritten in the background.