|Determine the Δ H of a reaction||Chemistry|
background [prelab assignment (35 points) due at the beginning of lab; put a copy in your lab NB]
1. calculate ΔH to dissolve solid NaOH in water (answer in kJ / mol) - theoretical value
2. based on the preceding calculation and ΔHfusion for water, calculate the amount of
to put into 100. mL of water to change the temperature by 10 °C [10 points].
3. what is the type of statistical test to be used to analysize such data ? review below links in use of stats software
4. describe the experimental design to examine the effect of
the amount of chemical
the nature of the calorimeter
on the accuracy in the experimental determination of the ΔH dissolve NaOH(s) in water and melting ice.
5. sketch a data table for this lab containing entries for all required experimental measurements to determine ΔH to __ [10 points]
- dissolve NaOH in water
- melt ice
6. msds information on sodium hydroxide
determine experimentally ΔH to:
- dissolve solid NaOH in water
- melt ice; i.e. find ΔHfusion for water
examine the effect of two experimental conditions on the accuracy of the determination of ΔH, then share class data among different groups.
fulfill various aspects of the NGSS science & engineering standards.
solid NaOH; ice; liquid water
coffee cup (calorimeter); thermometer; balance; gradulated cylinder, beaker
methods / analysis
student design - select 2 - 3 factors
anticipate about 1 - 2 weeks to complete the lab, which includes experimental design and data analysis.
Content of lab report (55 points)
data analysis (15 points)
data table of your group's experimental data
based on preceding data table, experimentally determine ΔH to __ ; show an example calculation
dissolve NaOH (in kJ / mole)
melt ice (in kJ / mole)
statistics [10 points; includes data entry / description, statistics test output, & type of statistics test]
disscussion [15 points]
factor(s) that affect the experimentally determined ΔH to dissolve NaOH and melt ice
support your claim based on the class experimental data / statistics
rationale / basis of the effect of the preceding factor(s)
reflection [15 poins]
describe / list three (std 1; std 2; std 3) NGSS science & engineering practices that correlates to an aspect of this laboratory activity; provide an example in the lab & this lab report that meets these practices
example lab: ΔH to dissolve NaOH
statistics: Vassar; Excel; minitab; mathematica