Calculation for Calorimetry

CALCULATIONS Determining the amount Limiting Reagent used. nlimiting reagent = Molarity x Volume or Mass / Molar Mass Example: Limiting reagent is 5mL of 1. 0 M HCl nlimiting reagent = Molarity x Volume nlimiting reagent = (1. 0 [mol/L]) x 0. 005 [L]) = 0. 005 mol Determining the qrxn and qcal. qrxn + qcal = 0 -qrxn = qcal qrxn = ? Hrxn x nlimiting reagent qcal = Ccal ? T qrxn = – Ccal ? T + mcsolid ? T (note: only if there is a precipitate formed in the reaction) Examples: 1) Calibration of the calorimeter given that: ?Hrxn = -55. 8 kJ/mol and nLR = 0. 005 mol qrxn = ? Hrxn x nlimiting reagent qrxn = -55. 8 [kJ/mol] x 0. 005 [mol] = -279 J qcal = -(219 J) = 279 J (2) Determining the qrxn of a given chemical reaction: NH3 (aq) + H+ (aq) ? NH4+ (aq) And given that: ? T = 3. 5 °C and Ccal=111. 6 J/°C qrxn = – Ccal ? T + mcsolid ? T qrxn = -( 111. 6 [kJ/°C] x 3. 5 [°C]) = -390. 6 J qcal = -(-390. 6 J) = 390. 6 Determining the Ccal. Ccal = qcal / ? T Example:

Given qrxn = -279 J and ? T = 2. 5 °C Ccal = -qrxn / ? T Ccal = -(-279 J) / (2. 5 °C) = 111. 6 J/°C Determining the experimental ? Hrxn. ?Hrxn = qrxn / nLR Example: Given: NH3 (aq) + H+ (aq) ? NH4+ (aq) With qrxn = -390. 6 J and nLR = 0. 005 mol ?Hrxn = qrxn / nLR ?Hrxn = -390. 6 J / 0. 005 mol = -78. 1 kJ/mol Determining the theoretical ? Hrxn. ?Hrxn = ? nproductH°f product – ? nreactantH°f reactant Example: Given that: NH3 (aq) + H+ (aq) ? NH4+ (aq) Substance? H°f (kJ/mol) NH3 (aq)-80. 9 H+ (aq)0. 00 NH4+ (aq)-132. 51 ?Hrxn = ? nproductH°f product – ? nreactantH°f reactant ? Hrxn = {-132. 51 kJ/mol}-{-80. 29 kJ/mol} = ?Hrxn = -52. 2 kJ/mol Determining the %error. %error = (|? Hexperimental – ? Htheoretical|) / (? Htheoretical) x 100% Example: Given: ? Hexperimental = -78. 1 kJ/mol and ? Htheoretical = -52. 2 kJ/mol %error = |(? Hexperimental – ? Htheoretical) / (? Htheoretical) | x 100% %error = |(-78. 1 kJ/mol) – (-52. 2 kJ/mol) / -52. 2 kJ/mol| x 100% = 49. 6 %

Basic features
• Free title page and bibliography
• Unlimited revisions
• Plagiarism-free guarantee
• Money-back guarantee
On-demand options
• Writer’s samples
• Part-by-part delivery
• Overnight delivery
• Copies of used sources
Paper format
• 275 words per page
• 12 pt Arial/Times New Roman
• Double line spacing
• Any citation style (APA, MLA, Chicago/Turabian, Harvard)

Our guarantees

At Solution Essays, we are determined to deliver high-quality papers to our clients at a fair price. To ensure this happens effectively, we have developed 5 beneficial guarantees. This guarantees will ensure you enjoy using our website which is secure and easy to use.

Money-back guarantee

Most companies do not offer a money-back guarantee but with Solution Essays, it’s either a quality paper or your money back. Our customers are assured of high-quality papers and thus there are very rare cases of refund requests due to quality concern.

Zero-plagiarism guarantee

All our papers are written from scratch and according to your specific paper instructions. This minimizes any chance of plagiarism. The papers are also passed through a plagiarism-detecting software thus ruling out any chance of plagiarism.

Free-revision policy

We offer free revisions in all orders delivered as long as there is no alteration in the initial order instruction. We will revise your paper until you are fully satisfied with the order delivered to you.

All data on our website is stored as per international data protection rules. This ensures that any personal data you share with us is stored safely. We never share your personal data with third parties without your consent.

Fair-cooperation guarantee

Ordering and sending money to us is an indication that you are purchasing our products and services. To have business talks laid out in the official language, you can check on our terms and conditions and get more information about this.

Calculate the price of your order

550 words
We'll send you the first draft for approval by September 11, 2018 at 10:52 AM
Total price:
\$26
The price is based on these factors: