This document provides a review for a chemistry final exam. It lists 27 topics that will be covered on the exam, with 70% of the exam focusing on material after the third partial. It also includes 7 practice problems covering various chemistry concepts like electron configurations, chemical reactions, stoichiometry, concentrations, and redox reactions. Students are advised to study their notes and practice problems in preparation for the comprehensive final exam.
INVESTIGATE THE PROPERTIES OF IONIC BOND AND COVALENT BOND THROUGH AN EXPERIMENTMISS ESTHER
CHEMISTRY FORM 4 KSSM
CHAPTER 5 : CHEMICAL BONDS (IONIC BOND AND COVALENT BOND)
EXPERIMENT 5.1 TO INVESTIGATE THE PROPERTIES OF IONIC BOND AND COVALENT BOND THROUGH EXPERIMENT
INVESTIGATE THE PROPERTIES OF IONIC BOND AND COVALENT BOND THROUGH AN EXPERIMENTMISS ESTHER
CHEMISTRY FORM 4 KSSM
CHAPTER 5 : CHEMICAL BONDS (IONIC BOND AND COVALENT BOND)
EXPERIMENT 5.1 TO INVESTIGATE THE PROPERTIES OF IONIC BOND AND COVALENT BOND THROUGH EXPERIMENT
Chapter 4 Problems1. Which of these compounds is a strong elec.docxketurahhazelhurst
Chapter 4 Problems
1.
Which of these compounds is a strong electrolyte?
A.
H2O
B.
O2
C.
H2SO4
D.
C6H12O6 (glucose)
E.
CH3COOH (acetic acid)
2. Which of these compounds is a nonelectrolyte?
A.
NaF
B.
HNO3
C.
CH3COOH (acetic acid)
D.
NaOH
E.
C6H12O6 (glucose)
3. Based on the solubility rules, which one of these compounds should be insoluble in water?
A.
NaCl
B.
MgBr2
C.
FeCl2
D.
AgBr
E.
ZnCl2
4. Based on the solubility rules, which of these processes will occur when a solution containing about 0.1 g of Pb(NO3)2(aq) is mixed with a solution containing 0.1 g of KI(aq)/100 mL?
A.
KNO3 will precipitate; Pb2+ and I- are spectator ions.
B.
No precipitate will form.
C.
Pb(NO3)2 will precipitate; K+ and I- are spectator ions.
D.
PbI2 will precipitate; K+ and NO3- are spectator ions.
E.
Pb2+ and I- are spectator ions, and PbI2 will precipitate.
5. Give the oxidation # for the following atoms:
a. N in NaNO3 _________
b. Mn in KMnO4 _________
c. Cl in ClO3- _________
6. Which of these equations does not represent an oxidation-reduction reaction?
A.
3Al + 6HCl ( 3H2 + AlCl3
B.
2H2O ( 2H2 + O2
C.
2NaCl + Pb(NO3)2 ( PbCl2 + 3NaNO3
D.
2NaI + Br2 ( 2NaBr + I2
E.
Cu(NO3)2 + Zn ( Zn(NO3)2 + Cu
7. What element is oxidized in the chemical reaction
NiO2 + Cd + 2H2O ( Ni(OH)2 + Cd(OH)2?
A.
Ni
B.
Cd
C.
O
D.
H
E.
This is not a redox reaction.
8. Which of these chemical equations describes a precipitation reaction?
A.
2H2(g) + O2(g) ( 2H2O(l)
B.
CaBr2(aq) + H2SO4(aq) ( CaSO4(s) + 2HBr(g)
C.
2KNO3(s) ( 2KNO2(s) + O2(g)
D.
2KBr(aq) + Cl2(g) ( 2KCl(aq) + Br2(l)
E.
2Al(s) + 3H2SO4(aq) ( Al2(SO4)3(aq) + 3H2(g)
9.
The common constituent in all acid solutions is
A.
H2.
B.
H+.
C.
OH-.
D.
H2SO4.
E.
Cl-.
10. Which of these chemical equations describes an acid-base neutralization reaction?
A.
2Al(s) + 3H2SO4(aq) ( Al2(SO4)3(aq) + 3H2(g)
B.
SO2(g) + H2O(l) ( H2SO3(g)
C.
LiOH(aq) + HNO3(aq) ( LiNO3(aq) + H2O(l)
D.
2KBr(aq) + Cl2(g) ( 2KCl(aq) + Br2(l)
E.
CaBr2(aq) + H2SO4(aq) ( CaSO4(s) + 2HBr(g)
11. Which of these chemical equations describes a combustion reaction?
A.
2C2H6(g) + 7O2(g) ( 4CO2(g) + 6H2O(l)
B.
LiOH(aq) + HNO3(aq) ( LiNO3(aq) + H2O(l)
C.
N2(g) + 3H2(g) ( 2NH3(g)
D.
2Na(s) + 2H2O(l) ( 2NaOH(aq) + H2(g)
E.
2Al(s) + 3H2SO4(aq) ( Al2(SO4)3(aq) + 3H2(g)
12.
What is the molarity of a solution that contains 5.0 moles of solute in 2.00 liters of solution?
13. What mass of K2CO3 is needed to prepare 200. mL of a solution having a concentration of 0.150 M?
14. A 50.0 mL sample of 0.436 M NH4NO3 is diluted with water to a total volume of 250.0 mL. What is the ammonium nitrate concentration in the resulting solution?
15. During a titration the following data were collected. A 10. mL portion of an unknown monoprotic acid solution was titrated with 1.0 M NaOH; 40. mL of the base were required to neutralize the sample. What is the molarity of the acid solution?
16. 34.62 mL of ...
Chapter 4 Problems1. Which of these compounds is a strong elec.docxrobertad6
Chapter 4 Problems
1.
Which of these compounds is a strong electrolyte?
A.
H2O
B.
O2
C.
H2SO4
D.
C6H12O6 (glucose)
E.
CH3COOH (acetic acid)
2. Which of these compounds is a nonelectrolyte?
A.
NaF
B.
HNO3
C.
CH3COOH (acetic acid)
D.
NaOH
E.
C6H12O6 (glucose)
3. Based on the solubility rules, which one of these compounds should be insoluble in water?
A.
NaCl
B.
MgBr2
C.
FeCl2
D.
AgBr
E.
ZnCl2
4. Based on the solubility rules, which of these processes will occur when a solution containing about 0.1 g of Pb(NO3)2(aq) is mixed with a solution containing 0.1 g of KI(aq)/100 mL?
A.
KNO3 will precipitate; Pb2+ and I- are spectator ions.
B.
No precipitate will form.
C.
Pb(NO3)2 will precipitate; K+ and I- are spectator ions.
D.
PbI2 will precipitate; K+ and NO3- are spectator ions.
E.
Pb2+ and I- are spectator ions, and PbI2 will precipitate.
5. Give the oxidation # for the following atoms:
a. N in NaNO3 _________
b. Mn in KMnO4 _________
c. Cl in ClO3- _________
6. Which of these equations does not represent an oxidation-reduction reaction?
A.
3Al + 6HCl ( 3H2 + AlCl3
B.
2H2O ( 2H2 + O2
C.
2NaCl + Pb(NO3)2 ( PbCl2 + 3NaNO3
D.
2NaI + Br2 ( 2NaBr + I2
E.
Cu(NO3)2 + Zn ( Zn(NO3)2 + Cu
7. What element is oxidized in the chemical reaction
NiO2 + Cd + 2H2O ( Ni(OH)2 + Cd(OH)2?
A.
Ni
B.
Cd
C.
O
D.
H
E.
This is not a redox reaction.
8. Which of these chemical equations describes a precipitation reaction?
A.
2H2(g) + O2(g) ( 2H2O(l)
B.
CaBr2(aq) + H2SO4(aq) ( CaSO4(s) + 2HBr(g)
C.
2KNO3(s) ( 2KNO2(s) + O2(g)
D.
2KBr(aq) + Cl2(g) ( 2KCl(aq) + Br2(l)
E.
2Al(s) + 3H2SO4(aq) ( Al2(SO4)3(aq) + 3H2(g)
9.
The common constituent in all acid solutions is
A.
H2.
B.
H+.
C.
OH-.
D.
H2SO4.
E.
Cl-.
10. Which of these chemical equations describes an acid-base neutralization reaction?
A.
2Al(s) + 3H2SO4(aq) ( Al2(SO4)3(aq) + 3H2(g)
B.
SO2(g) + H2O(l) ( H2SO3(g)
C.
LiOH(aq) + HNO3(aq) ( LiNO3(aq) + H2O(l)
D.
2KBr(aq) + Cl2(g) ( 2KCl(aq) + Br2(l)
E.
CaBr2(aq) + H2SO4(aq) ( CaSO4(s) + 2HBr(g)
11. Which of these chemical equations describes a combustion reaction?
A.
2C2H6(g) + 7O2(g) ( 4CO2(g) + 6H2O(l)
B.
LiOH(aq) + HNO3(aq) ( LiNO3(aq) + H2O(l)
C.
N2(g) + 3H2(g) ( 2NH3(g)
D.
2Na(s) + 2H2O(l) ( 2NaOH(aq) + H2(g)
E.
2Al(s) + 3H2SO4(aq) ( Al2(SO4)3(aq) + 3H2(g)
12.
What is the molarity of a solution that contains 5.0 moles of solute in 2.00 liters of solution?
13. What mass of K2CO3 is needed to prepare 200. mL of a solution having a concentration of 0.150 M?
14. A 50.0 mL sample of 0.436 M NH4NO3 is diluted with water to a total volume of 250.0 mL. What is the ammonium nitrate concentration in the resulting solution?
15. During a titration the following data were collected. A 10. mL portion of an unknown monoprotic acid solution was titrated with 1.0 M NaOH; 40. mL of the base were required to neutralize the sample. What is the molarity of the acid solution?
16. 34.62 mL of.
ENG 107 Commentary 1HW for Tu, April 19th – Commentary .docxSALU18
ENG 107 Commentary 1
HW for Tu, April 19th – Commentary Paper Proposal
1. Choose the trend about which you will be writing your commentary.
2. Go to Google / images; type “you trend name stats” and find a recent chart/graph that represents this trend. Note, you graph has to come with an article.
3. Examine the chart/graph; try to read it and understand what it says.
4. Write a 1p. long Paper Proposal.
1. Insert the graph/chart
2. Write 1 paragraph in which you introduce and explain this graph to us.
i. The graph on Figure 1 represents the trend of …..(name the trend). The graph was made ion …. by…. This graph shows …. . We can also see that ….. Another obvious tendency shown in this graph is that …. . Finally, it is evident that ….
ii. The information presented in this trend made me think that ….
3. What is the significance of this trend? Why did you choose to write your commentary about this trend?
4. Read the article that comes with the trend. Write a short annotation to this article:
· You introduce your source:
I found an article (a website) on the Internet written (created) by ………..and publishedin (a newspaper) /on (a website) in… (date).
· Briefly summarize the main idea of the article:
From this article I learned that… . I also discovered that …. … . It was new to me that … Likewise I found out that... It turns out that… Moreover, I learned that… So-So’s (name of the author) article made me wonder… / think of … (Author’s Last Name / “Title of the Article”).
· Quote one or 2 sentences that you found especially interesting.
I found it especially interesting that So-So (author) says/ believes/ suggests/… that “……..your quotation goes here” (Author’s Last Name / “Title of the Article”).
· Your commentary / response to the article:
These words made me think that….
1
Practice Problems -- Set #4 (chap 9 and 10)
1. MgCl2 is a(an)
(A). acid
(B). base
(C). salt
(D). covalent compound
2. Which one of the compounds is insoluble in water (hint: solubility rules)
(A). BaSO4
(B). NaCl
(C). KI
(D). HCl
(E). All of the above are soluble in water.
3. Identify a strong base.
(A). HNO3
(B). KCl
(C). NH4OH
(D). NaOH
(E). Na2SO4
4. Acid-base reaction is a neutralization reaction. If 12.50 mL of 1.20 M NaOH solution is used to
neutralize 45.25 mL of HNO3 solution, calculate the concentration of the original HNO3
solution.
(A). 0.231 M
(B). 0.995 M
(C). 0.887 M
(D). 0.331 M
(E). 9.90 M
5. Acid-base reaction is a neutralization reaction. If 12.50 mL of 1.20 M NaOH solution is used to
neutralize 45.25 mL of H2SO4 solution, calculate the concentration of the original H2SO4
solution.
2NaOH + H2SO4 Na2SO4 + 2H2O (balanced?)
(A). 0.231 M
(B). 0.995 M
(C). 0.887 M
(D). 0.166 M
(E). 0.331 M
6. Oxidation-reduction (redox) reactions involve electrons. If an element in ground state loses two
electrons during the redox reaction, this process ...
https://www.deped.gov.ph/wp-content/uploads/2019/01/General-Chemistry-1-and-2.pdf
General Chemistry
GenChem
STEM
Science, Technology, Engineering, and Mathematics
K to 12 Senior High School STEM Specialized Subject – General Chemistry 1 and 2
Quarter 1 – General Chemistry 1
Matter and Its Properties
Measurements
Atoms, Molecules and Ions
Stoichiometry
Percent Composition and Chemical Formulas
Chemical reactions and chemical equations
Mass Relationships in Chemical Reactions
Gases
Dalton’s Law of partial pressures
Gas stoichiometry
Kinetic molecular theory of gases
Quarter 2 – General Chemistry 1
Electronic Structure of Atoms
Electronic Structure and Periodicity
Chemical Bonding
Organic compounds
Quarter 3 – General Chemistry 2
Intermolecular Forces and Liquids and Solids
Physical Properties of Solutions
Thermochemistry
Chemical Kinetics
Quarter 4 – General Chemistry 2
Chemical Thermodynamics
Chemical Equilibrium
Acid-Base Equilibria and Salt Equilibria
Electrochemistry
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.
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.
"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.
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/
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
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
DevOps and Testing slides at DASA ConnectKari Kakkonen
My and Rik Marselis slides at 30.5.2024 DASA Connect conference. We discuss about what is testing, then what is agile testing and finally what is Testing in DevOps. Finally we had lovely workshop with the participants trying to find out different ways to think about quality and testing in different parts of the DevOps infinity loop.
Slack (or Teams) Automation for Bonterra Impact Management (fka Social Soluti...Jeffrey Haguewood
Sidekick Solutions uses Bonterra Impact Management (fka Social Solutions Apricot) and automation solutions to integrate data for business workflows.
We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
This video focuses on the notifications, alerts, and approval requests using Slack for Bonterra Impact Management. The solutions covered in this webinar can also be deployed for Microsoft Teams.
Interested in deploying notification automations for Bonterra Impact Management? Contact us at sales@sidekicksolutionsllc.com to discuss next steps.
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.
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.
FIDO Alliance Osaka Seminar: Passkeys and the Road Ahead.pdf
Final exam review
1. November 23rd, 2011
Final Exam Review
This is the review for the final exam. It by no means intends to depict
the exam’s format, and it is NOT everything you need to know for the
final exam. This review is intended to help you have more chemistry
practice. Below I have written the topics we have covered this
semester (I may have missed some, but you SHOULD have all of
them in your notes!The old reviews should help you study as well.
Make sure you go over your notes and homework. Do not wait until
the day before the exam to study, begin now!
70 percent of the exam will be based on the material covered after
third partial.
10 percent will come from first partial.
10 percent will come from second partial.
10 percent will come from third partial.
For a total of 100 percent
1. Introduction to chemistry: definition of chemistry
2. Matter
3. Substance
4. Mass vs. Weight
5. Conversions (SI Units and English Units)
6. Properties and changes of matter (physical and chemical…
include states of matter)
7. Elements name and symbol of common elements
8. Methods of separating mixtures
9. Types of mixtures
10. The atom and the atomic model
11. Atomic structure (composition, atomic mass, atomic number,
average atomic mass)
12. Ions
13. Isotopes
14. Atomic models
15. Ground vs. Excited State
16. Quantum numbers
17. Electron configurations
18. Periodic Table and periodic trends
19. Types of bonds
20. Types of inorganic compounds
2. November 23rd, 2011
Final Exam Review
21. Types of reactions
22. Nomenclature
23. Oxidation Numbers
24. Balancing (This will include Redox)
25. Stoichiometry
26. Ideal Gas Law
27. Solutions
28. Concentrations
29. pH
Solve the following problems:
1. Draw the orbital diagram, the electron configuration, electron dot notation, and
the noble notation of the following elements. Then find the four quantum numbers
for the given electron.
a. Re (hint this element goes through the f-orbitals): 30th electron
b. Cd: 14th electron
c. Ra: 83rd electron
d. In: 36th electron
2. Differentiate between chemical and physical property and change, give
examples of each.
3.Give the names of the following compounds and find the oxidation numbers.
a. Ca(C2H3O2)2
b. NO2
c. SiF4
d. VCl5
4. Complete the following reactions, state the type of reaction and balance where
necessary, identify the type of inorganic compound:
a. K(s) + Cl2(g)
b. H2CO3
c. MCO3
d. Fe(s) + CuSO4(aq)
e. AgNO3(aq) + KCl(aq)
f. HCl (aq) + NaOH (aq)
g. HBr (aq) + Ba(OH)2 (aq)
3. November 23rd, 2011
Final Exam Review
5. Stoichiometry
a. Ethanol, also known as grain, can be made from the
fermentation of sugar (C6H12O6). The unbalanced chemical equation for the
reaction is shown below.
C6H12O6 C2H5OH + CO2
Balance the chemical equation and determine the mass of C2H5OH produced
from 750 g of C6H12O6.
b. Hydrofluoric acid solutions cannot be stored in glass containers
because HF reacts readily with silica dioxide in glass to produce hexafluorosilicic
acid (H2SiF6). 40.0g SiO2 and 40.0g HF react to yield 45.8 g H2SiF6.
SiO2 (s) + 6HF (aq) H2SiF6 (aq) + 2H2O (l)
I. What is the limiting reactant?
II. What is the mass of the excess reactant?
III. What is the theoretical yield of H2SiF6?
IV. What is the percent yield?
c. This problem is a challenge problem, harder than the ones we
have done before… but not so hard as to where you cannot answer it. Read the
problem carefully!
Phosphorus (P4) is commercially prepared by heating a mixture of calcium
phosphate (Ca3(PO4)2), sand (SiO2), and coke (C) in an electric furnace. The
process involves two reactions.
2Ca3(PO4)2 (s) + 6SiO2 (s) 6CaSiO3 (l) + P4O10 (g)
P4O10 (g) + 10C (s) P4 + 10CO (g)
The P4O10 produced in the first reaction reacts with an excess of coke (C) in the
second reaction. Determine the theoretical yield P4if 250.0 g of Ca3(PO4)2and
400.0 g of SiO2are heated. If the actual yield of P4 is 45.0g, determine the
percent yield of P4.
4. November 23rd, 2011
Final Exam Review
6. Concentrations
a. What mass of NaOH is in 250 mL of a 3.OM NaOH solution?
b. How many milliliters of a 5.0 M H2SO4 stock solution would you
need to prepare 100.0mL of 0.15M H2SO4?
c. What is the molality of a solution that contains 75.3 g of KCl
dissolved in 95.0 g of water?
d. How many grams of Na2CO3 must be dissolved into 155 g of
water to create a solution with a molality of 8.20 mol/kg?
e. This is also a challenge problem. Hint fin the moles and then
use stoichiometry to solve for the rest of it… What volume of
ethanol (C2H3OH) is in a 100.0 mL of 0.15 M solution? The
density of ethanol is 0.7893 g/mL.
7. Balance the following equations using redox
a. Identify each of the following as either oxidation or reduction.
1. I2 + e- 2I- 2. Fe2+Fe3+ + e-
3. K K+ + e- 4. Ag+ +e- Ag
b. Identify what is being oxidized and what is being reduced
i. 2Br- + Cl2 Br2 + Cl-
ii. 2Zn + O2 2ZnO
iii. 2Na + 2H+ 2Na+ + H2
c. Balance the following reactions using Redox:
i. Fe + CuSO4 FeSO4 + Cu
ii. Fe + HBr H2 + FeBr3