The document discusses moles, molar mass, and empirical and molecular formulas.
It defines key terms like mole, Avogadro's number, and molar mass. A mole represents 6.02x1023 particles of a substance. Molar mass is the mass in grams of one mole of a substance.
Examples are provided for calculating moles from mass and vice versa using molar mass. Empirical formulas represent the lowest whole number ratio of elements in a compound, while molecular formulas specify the actual number of each atom in a molecule or formula unit.
A chemical reaction describes what occurs in a chemical change. It shows not only the kind but also the relative amounts of the substances involved in a change. The coefficients written before the formulas in a balanced equation represent the number of moles of each substance involved in a reaction. Since the number of moles is related to the mass of any substance and to the volume of any gaseous substance, the mole relationship can be easily changed to mass/volume relationship. The concepts on how to calculate molarity, molality and normality are important in identifying the relative amounts of the substances involved in a chemical reaction.
SHS STEM General Chemistry 1: Atoms, Moles, Equations, StoichiometryPaula Marie Llido
HS STEM General Chemistry 1: Atoms, Moles, Equations, Stoichiometry
-Atomic Mass
-Empirical and Molecular Formula
-Percent Composition
-Mole, Molar Mass, and Atom Conversion
-Chemical Reaction and Equation
-Mass Relationships in Chem Reactions
-Stoichiometry
-Limiting and Excess Reagent
-Percent Yield
A chemical reaction describes what occurs in a chemical change. It shows not only the kind but also the relative amounts of the substances involved in a change. The coefficients written before the formulas in a balanced equation represent the number of moles of each substance involved in a reaction. Since the number of moles is related to the mass of any substance and to the volume of any gaseous substance, the mole relationship can be easily changed to mass/volume relationship. The concepts on how to calculate molarity, molality and normality are important in identifying the relative amounts of the substances involved in a chemical reaction.
SHS STEM General Chemistry 1: Atoms, Moles, Equations, StoichiometryPaula Marie Llido
HS STEM General Chemistry 1: Atoms, Moles, Equations, Stoichiometry
-Atomic Mass
-Empirical and Molecular Formula
-Percent Composition
-Mole, Molar Mass, and Atom Conversion
-Chemical Reaction and Equation
-Mass Relationships in Chem Reactions
-Stoichiometry
-Limiting and Excess Reagent
-Percent Yield
How Do I Calculate Substance Values? (for Chemical Analysis & Reporting)raj takhar
This document is part of a series of LinkedIn posts authored by myself entitled “Searching the path towards sustainable chemical substance reporting.”
This presentation focuses on examples of analysing data.
The aim is to get viewer input on best practices for determining surface area and substance analysis. Once the best practices have identified, then a freeware tool will be created to help everyone.
Experiment with natural nanomaterials - nanotechnologyNANOYOU
n this experiment you will analyse some innovative materials that are highly water repellent, stainless and require less cleaning thanks to their surface nano-engineering. Those materials have been developed using nature as an inspiration, since some plant leaves have exceptional properties due to their surface composition.
The property you will analyse is the superhydrophobic effect found in some leaves, such as the lotus leaf. The effect is due to interplay of surface chemistry and surface topography at the micro- and nano-level. Download the documents below to carry out the experiment and watch the information videos available below.
Translations to several languages are also availabe in the NANOYOU website.
All over the years researchers have dicovered and created new materials through the study of bonds, that have been useful in many fields such as medicine, agriculture, industry, communications, construction, among others.
Chemistry word can be represented as C for chemistry, H for health, E for environment, M for medicines, I for industries, S for sciences, T for teaching, R for research and Y for you.
we are a living chemistry as we are made of chemicals only and there are a lot of chemical reactions going in our body.
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
In this insightful webinar, Inflectra explores how artificial intelligence (AI) is transforming software development and testing. Discover how AI-powered tools are revolutionizing every stage of the software development lifecycle (SDLC), from design and prototyping to testing, deployment, and monitoring.
Learn about:
• The Future of Testing: How AI is shifting testing towards verification, analysis, and higher-level skills, while reducing repetitive tasks.
• Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
"Impact of front-end architecture on development cost", Viktor TurskyiFwdays
I have heard many times that architecture is not important for the front-end. Also, many times I have seen how developers implement features on the front-end just following the standard rules for a framework and think that this is enough to successfully launch the project, and then the project fails. How to prevent this and what approach to choose? I have launched dozens of complex projects and during the talk we will analyze which approaches have worked for me and which have not.
Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
UiPath Test Automation using UiPath Test Suite series, part 4DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 4. In this session, we will cover Test Manager overview along with SAP heatmap.
The UiPath Test Manager overview with SAP heatmap webinar offers a concise yet comprehensive exploration of the role of a Test Manager within SAP environments, coupled with the utilization of heatmaps for effective testing strategies.
Participants will gain insights into the responsibilities, challenges, and best practices associated with test management in SAP projects. Additionally, the webinar delves into the significance of heatmaps as a visual aid for identifying testing priorities, areas of risk, and resource allocation within SAP landscapes. Through this session, attendees can expect to enhance their understanding of test management principles while learning practical approaches to optimize testing processes in SAP environments using heatmap visualization techniques
What will you get from this session?
1. Insights into SAP testing best practices
2. Heatmap utilization for testing
3. Optimization of testing processes
4. Demo
Topics covered:
Execution from the test manager
Orchestrator execution result
Defect reporting
SAP heatmap example with demo
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Search and Society: Reimagining Information Access for Radical FuturesBhaskar Mitra
The field of Information retrieval (IR) is currently undergoing a transformative shift, at least partly due to the emerging applications of generative AI to information access. In this talk, we will deliberate on the sociotechnical implications of generative AI for information access. We will argue that there is both a critical necessity and an exciting opportunity for the IR community to re-center our research agendas on societal needs while dismantling the artificial separation between the work on fairness, accountability, transparency, and ethics in IR and the rest of IR research. Instead of adopting a reactionary strategy of trying to mitigate potential social harms from emerging technologies, the community should aim to proactively set the research agenda for the kinds of systems we should build inspired by diverse explicitly stated sociotechnical imaginaries. The sociotechnical imaginaries that underpin the design and development of information access technologies needs to be explicitly articulated, and we need to develop theories of change in context of these diverse perspectives. Our guiding future imaginaries must be informed by other academic fields, such as democratic theory and critical theory, and should be co-developed with social science scholars, legal scholars, civil rights and social justice activists, and artists, among others.
Kubernetes & AI - Beauty and the Beast !?! @KCD Istanbul 2024Tobias Schneck
As AI technology is pushing into IT I was wondering myself, as an “infrastructure container kubernetes guy”, how get this fancy AI technology get managed from an infrastructure operational view? Is it possible to apply our lovely cloud native principals as well? What benefit’s both technologies could bring to each other?
Let me take this questions and provide you a short journey through existing deployment models and use cases for AI software. On practical examples, we discuss what cloud/on-premise strategy we may need for applying it to our own infrastructure to get it to work from an enterprise perspective. I want to give an overview about infrastructure requirements and technologies, what could be beneficial or limiting your AI use cases in an enterprise environment. An interactive Demo will give you some insides, what approaches I got already working for real.
UiPath Test Automation using UiPath Test Suite series, part 3DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 3. In this session, we will cover desktop automation along with UI automation.
Topics covered:
UI automation Introduction,
UI automation Sample
Desktop automation flow
Pradeep Chinnala, Senior Consultant Automation Developer @WonderBotz and UiPath MVP
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Accelerate your Kubernetes clusters with Varnish CachingThijs Feryn
A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
2. Counting Matter What are some everyday ways we count matter? 1. 2. 3. DOZEN = 12 things 1 GROSS = 144 things What about molecules? Or atoms? BUSHEL of corn = 21.772 kg 1 MOLE = ???
3. The Mole It represents a counted number of things. IN Chemistry the term MOLE represents the number of particles in a substance. In Chemistry is NOT this furry little animal or the spot on your face…
4. Just how many is a mole? One mole represents 6.02 x 1023 of things (units, molecules, compounds, formula units). This is called Avogadro’s number. One mole of most elements contains 6.02 x 1023atoms. 1 mole O2 = 6.02x1023molecules of O2 602 000 000 000 000 000 000 000
5. Just how big is a mole? Listen to The Mole Song! An Avogadro's number of standard soft drink cans would cover the surface of the earth to a depth of over 200 miles If you had Avogadro's number of un-popped popcorn kernels, and spread them across the United States of America, the country would be covered in popcorn to a depth of over 9 miles. If we were able to count atoms at the rate of 10 million per second, it would take about 2 billion years to count the atoms in one mole.
6. Solving the Problems Samples Required: dimensional analysis/factor label How many molecules are in 3.00 moles of N2? How many moles of Na are in 1.10 x 1023 atoms?
7. Practice moles to particles Determine the number of atoms in 2.50 mol Zn. Given 3.25 mol AgNO3, determine the number of formula units. Calculate the number of molecules in 11.5 mol H2O.
8. Practice Particles to Moles How many moles contain each of the following? 5.75 x 1024 atoms Al 3.75 x 1024 molecules CO2 3.58 x 1023 formula units ZnCl2 2.50 x 1020 atoms Fe
10. Molar Mass Defn: is the mass (think grams) of one mole of a substance Atomic masses (from periodic table) represent molar mass. Units g/mol 1 moleof Carbon has 6.02 x 1023 atoms of C and they have a mass of12.01grams. To calculate the molar mass of a compound, you add up the molar masses of all the elements in that compound
11. Molar Mass Practice What is the mass of 1.00 mole of Oxygen? Of Nitrogen? Find the molar mass for: SO3 Na2SO4 1 mole O = 16.0 grams 1 mole N = 14.0 grams SO3= 80 g/mole 1 Mole = 142.043g Tutorial Site Molar Mass Calculator for homework help
12. Molar Mass Practice When you see 1.00 mole = _?_ g, think “g means GO to the PERIODIC TABLE” to find the molar mass. http://www.webelements.com/
13. Practice Problems Determine the molar mass of each of the following ionic compounds: NaOH CaCl2 KC2H3O2 HCN CCl4 H2O
15. Practice Mole to Grams Determine the mass in grams of each of the following. 3.57 mol Al 42.6 mol Si 3.45 mol Co 2.45 mol Zn
16. Practice Gram to Mole How many atoms are in each of the following samples? 55.2 g Li 0.230 g Pb 11.5 g Hg 45.6 g Si 0.120 kg Ti
17. Ex: Mass to Particle Conversion Gold is one of a group of metals called the coinage metals (copper, silver and gold). How many atoms of gold (Au) are in a pure gold nugget having a mass of 25.0 g? Known:Unknown: Mass = 25.0 g Au Molar mass Au = 196.97 g/mol Au 25.0 g Au x 1 mole Au x 6.02 x 1023 atoms Au = 7.65 x 1022 atoms Au 196.97 g Au 1 mol Au Number of atoms = ? Atoms Au
18. Practice Problems How many atoms are in each of the following samples? 55.2 g Li 0.230 g Pb 11.5 g Hg 45.6 g Si 0.120 kg Ti
19. Ex: Particle to Mass Conversion A party balloon contains 5.50 x 1022 atoms of helium (He) gas. What is the mass in grams of the helium? Known:Unknown: Number of atoms = 5.50 x 1022 atoms He Molar mass He = 4.00 g/mol He 5.50 x 1022 atoms He x 1 mol He x 4.00 g He = 0.366 g He 6.02 x 1023 atoms He 1 mol He Mass = ? G He
20. Practice Problems What is the mass in grams of each of the following? 6.02 x 1024 atoms Bi 1.00 x 1024 atoms Mn 3.40 x 1022 atoms He 1.50 x 1015 atoms N 1.50 x 1015 atoms U
21. Molar Volume The volume of a gas is usually measured at standard temperature and pressure (_STP_) Standard temp = ___0°_ C Standard pressure = ___1___ atmosphere (atm) 1 mole of any gas occupies __22.4__ L of space at STP
22. Molar Volume Practice How many moles would 45.0 L of He gas be? How many liters of O2 would 3.8 moles occupy?
23. Putting it all together 1.0 mole = _6.02 x 1023___atoms or molecules 1.0 mole = _?__ g(PT) 1.0 mole= _22.4 L (at STP)
25. Chemical Formulas and the Mole Chemical formula for a compound indicates the types of atoms and the number of each contained in one unit. Ex. CCl2F2 - Freon Ratio of carbon to chlorine to fluorine is 1:2:2 Ratios can be written: or In one mole of freon you would have 1 mole of carbon, 2 moles of chlorine and 2 moles of fluorine.
26. Ex: Mole Relationship from Chemical Formulas Determine the moles of aluminum ions (Al3+) in 1.25 moles of aluminum oxide 1.25 molAl2O3 x 2 mol Al3+ ions = 2.50 mol Al3+ ions 1 mole Al2O3
27. Practice Problems Determine the number of moles of chloride ions in 2.53 mol ZnCl2. Calculate the number of moles of each element in 1.25 mol glucose (C6H12O6). Determine the number of moles of sulfate ions present in 3.00 mol iron (III) sulfate (Fe(SO4)3). How many moles of oxygen atoms are present in 5.00 mol diphosphoruspentoxide? Calculate the number of moles of hydrogen atoms in 11.5 mol water.
28. Practice Problems A sample of silver chromate has a mass of 25.8 g. How many Ag+ ions are present? How many CrO42- ions are present? What is the mass in grams of one unit of silver chromate? What mass of sodium chloride contains 4.59 x 1024 units? A sample of ethanol (C2H5OH) has a mass of 45.6 g. How many carbon atoms does the sample contain? How many hydrogen atoms are present? How many oxygen atoms are present?
30. Percent Composition the percentage by mass of each element in a compound The percent comp. is found by using the following formula:
31. Percent Composition Example Ex. Compound XY is 55g element X and 45g element Y 55 g of element Xx 100 = 55 % element X 100 g of compound 45 g of element Y x 100 = 45 % element Y 100 g of compound
32. Percent Composition from Chemical Formula First find the molar mass of each element and the molar mass of the compound Ex: what is the % composition of H in 1 mole of H2O? Multiply the molar mass of the element by its subscript in the formula. 1.01 g/mol H x 2 mol = 2.02 g H % by mass H = 2.02 g x 100 = 11.2% H 18.02 g H2O
33. Percent Composition from Chemical Formula Example continued – Molar mass of O for each mole of H2O? 16.00 g/mol O x 1mol O = 16.00 g O 16.00 g x 100 = 88.8 % O 18.02 g
34. % Composition Practice What is the percent of C & H in C2H6? What is the percent of each element in Na2SO3?
35. Empirical Formulas This is the LOWEST whole number ratio of the elements in a compound. For example, the empirical formula for Molecular Formula C6H6 Empirical Formula CH What is the empirical formula for each? C2H6 C6H12O6
36.
37. Example Using Percent Composition The percent composition of an oxide of sulfur is 40.05% S and 59.95% O. Assuming you have a 100g sample, it contains 40.05g S and 59.95g O. Convert to moles using molar mass: 40.05g S x 1 mol = 1.249 mol S 32.07g 59.95g O x 1 mol = 3.747 mol O 16.00g
38. Example Using Percent Composition The mole ratio of S atoms to O atoms in the oxide is 1.249 : 3.747. Recognize that S has the smallest possible number of moles at ~1. Make the mole value of S equal to 1 by dividing both mole values by 1.249. 1.249 mol S = 1 mol S 1.249 3.747 mol O = 3 mol O 1.249 The simplest whole number mole ratio of S atoms to O atoms is 1 : 3. The empirical formula for the oxide of sulfur is SO3.
39. Sample Problems What is the empirical formula for a compound which is 75 % C and 25 % H? What is the empirical formula for a compound which has 48.64 % C, 8.16 % H 43.20 % O
40. Sample Problems #2 What is the empirical formula of 40.68 % C 5.08 % H 54.24 % O
41. Practice Problems A blue solid is found to contain 36.894% N and 63.16% O. What is the empirical formula for this solid? Determine the empirical formula for a compound that contains 35.98% Al and 64.02% S. Propane is a hydrocarbon, a compound composed only of carbon and hydrogen. It is 81.82% C and 18.18% H. What is the empirical formula? The chemical analysis of aspirin indicates that the molecule is 60.00% C, 4.44% H and 35.56% O. Determine the empirical formula. What is the empirical formula for a compound that contains 10.89% Mg, 31.77% Cl, and 57.34% O?
42. Molecular Formula Specifies the actual number of atoms of each element in one molecule or formula unit of the substance n= ratio between experimentally determined mass of compound and the molar mass of the empirical formula.
43. Calculating Molecular Formula Molar mass of acetylene – 26.04 g/mol Mass of empirical formula (CH) – 13.02 g/mol n – Obtained by dividing the molar mass by the mass of the empirical formula indicates that the molar mass of acetylene is two times the mass of the empirical formula. Experimentally determined molar mass of acetylene = 26.04 g/mol = 2.000 mass of empirical formula CH 13.02 g/mol Molecular Formula = (CH)2 Acetylene = C2H2
44. Determining a Molecular Formula Succinic acid is a substance produced by lichens. Chemical analysis indicates it is composed of 40.68% C, 5.08% H, and 54.24% O and has a molar mass of 118.1 g/mol. Determine the empirical and molecular formulas for succinic acid. Known: Unknown: Percent by mass = 40.68% C empirical formula = ? Percent by mass = 5.08% H molecular formula = ? Percent by mass = 54.24% O
45. Practice Problems Analysis of a chemical used in photographic developing fluid indicates a chemical composition of 65.45% C, 5.45% H, and 29.09% O. The molar mass is found to be 110.0 g/mol. Determine the molecular formula. A compound was found to contain 49.98 g C, and 10.47 g H. The molar mass of the compound is 58.12 g/mol. Determine the molecular formula. A colorless liquid composed of 46.68% N and 53.32% O has a molar mass of 60.01 g/mol. What is the molecular formula?
47. Naming Hydrates Hydrate: a compound that has a specific number of water molecules bound to its atoms. In the formula for a hydrate, the number of water molecules associated with each formula unit of the compound is written following a dot. ex. Na2CO3·10H2O called sodium carbonate decahydrate deca- means 10 and hydrate means water Therefore there are 10 water molecules are associated with one formula unit of the compound.
49. Analyzing a Hydrate Must drive off the water by heating the compound Substance remaining after heating is anhydrous (without water) Example: hydrated cobalt(II) chloride is a pink solid that turns a deep blue when the water of hydration is driven off and anhydrous cobalt(II) chloride is produced
50. Formula for a Hydrate To determine the formula for a hydrate, you must determine the number of moles of water associated with one mole of the hydrate.
51. Example Problem – Determining the Formula for a Hydrate A mass of 2.5 g of blue, hydrated copper sulfate (CuSO4·xH2O) is placed in a crucible and heated. After heating, 1.59 g white anhydrous copper sulfate (CuSO4) remains. What is the formula for the hydrate? Name the hydrate.
52. Example Problem – (cont.) Known: Mass of hydrated compound = 2.50 g CuSO4·xH2O Mass of anhydrous compound = 1.59 g CuSO4 Molar mass = 18.02 g/mol H2O Molar mass = 159.6 g/mol CuSO4 Unknown: Formula for hydrate = ? Name of hydrate = ?
53. Example Problem – (cont.) Subtract the mass of the anhydrous copper sulfate from the mass of the hydrated copper sulfate to determine the mass of water lost: mass of hydrates copper sulfate 2.50 g mass of anhydrous copper sulfate - 1.59 g mass of water lost 0.91 g Calculate the number of moles of H2O and anhydrous CuSO4 1.59 g CuSO4 x 1 mol CuSO4 = 0.00996 mol CuSO4 159.6 g CuSO4 0.91 g H2O x 1 mol H2O = 0.050 mol H2O 18.02 g H2O
54. Example Problem – (cont.) Determine the value of x. x = moles H2O = 0.050 mol H2O = 5.0 mol H2O = 5 moles CuSO4 0.00996 mol CuSO4 1.0 mol CuSO4 1 The ratio of H2O to CuSO4 is 5 : 1, so the formula for the hydrate is CuSO4·5H2O, copper(II) sulfate pentahydrate.
55. Practice Problems A hydrate is found to have the following percent composition: 48.18% MgSO4 and 51.2% H2O. What is the formula and name for this hydrate? If 11.75 g of the common hydrate cobalt(II) chloride is heated, 9.25 g of anhydrous cobalt chloride remains. What is the formula and name for this hydrate?
56. Uses of Hydrates Drying agents: CaCl2, CaSO4 Storage of solar energy: Na2SO4·10H2O