This document contains a sample exam paper for a Level 1 Science exam on acids and bases. The exam consists of 4 questions. Question 1 asks students to explain why magnesium and calcium form ions with a charge of +2 and to complete information about sodium and beryllium ions. Question 2 asks about isotopes of lithium and beryllium. Question 3 describes an acid-base reaction using indicators and asks students to explain the observations. Question 4 describes a reaction between marble chips and hydrochloric acid and asks students to explain the rate of reaction and effects of powdering the marble. The exam paper provides space for students to show their work and additional pages in the back if more space is needed to answer questions fully
Synthesis and Application of C-Phenylcalix[4]resorcinarene in Adsorption of C...Jacsonline.Org
Synthesis and Application of C-Phenylcalix[4]resorcinarene in Adsorption of Cr(III) and Pb(II), for more information visit our website http://jacsonline.org/
Synthesis and Application of C-Phenylcalix[4]resorcinarene in Adsorption of C...Jacsonline.Org
Synthesis and Application of C-Phenylcalix[4]resorcinarene in Adsorption of Cr(III) and Pb(II), for more information visit our website http://jacsonline.org/
I have discussed complete guess of long questions form 9th class chemistry. Notes of other classes are also available #competitive chemistry exams. Easy teaching method. After learning the above questions students of 9th grade chemistry will be able to learn chemistry. I have done my M.phil chemistry from Punjab university Lahore. Here I will discuss every Chemistry topic related to thier syllabus. Feel free to contact me on my Gmail
rashidahnd786@gmail.com.
I am silver medalist in M.phil physical chemistry. I will try my best to convey material regarding chemistry.
Organic I Review Workbook – The Toolbox ALL STAR MOLECU.docxjacksnathalie
Organic I Review Workbook – The Toolbox
ALL “STAR MOLECULES” () SHOULD BE ORGANIZED AND EMPHASIZED AS THEY CAN
BE CALLED UPON AT ANY MOMENT THROUGHOUT THE COURSE. THEY SHOULD BE
KNOWN BY THEIR STAR/COMMON NAME, IUPAC NOMENCLATURE, LINE ANGLE
STRUCTURE, ACRONYM, SHORTHAND NOTATION, FAVORITE FLAVOR OF ICE CREAM,
FAVORITE ONE REPUBLIC SONG, ETC.
1. Review Basic Geometries/Hybridization/Bonding
Questions:
a) Does the electronegativity of a carbon atom increase or decrease with increasing p-
character? Use acetylene and ethylene as examples to help explain your
reasoning. Still stuck? Table 4.1 may provide even more assistance.
b) What is more nucleophilic, a carbon-carbon bond or bond?
c) What is lower in energy, the * orbital or * orbital of a C=C bond?
d) Are the orbitals described in part c) representative of electrophiles or nucleophiles?
e) A lone pair must be in what kind of orbital(s) in order to participate in
resonance/conjugation? s, p, sp, sp2 or sp3. Choose all that apply.
2. Functional Group Recognition / Functional Group Transformation (A+B = C)
Alkene Aldehyde Glycol
Alkyl halide Carboxylic Acid Ketone
Alcohol (alkyl vs aryl) Ether Nitrile
Amine (1°, 2°, 3°) Ester Sulfide
Alkyne Epoxide Thiol
Amide (1°, 2°, 3°) Enol
Questions:
a) Which functional groups above contain the carbonyl/acyl group?
b) Is the carbonyl/acyl carbon of a ketone electrophilic or nucleophilic?
c) All things being equal, which functional group is the most Bronsted acidic (not
including the carboxylic acid)?
d) The transformation of a functional group can be described as a single functional group
starting material (A) being added to a selective environment (B) to generate a new
functional group (C). Basically, A+B = C. With this in mind, which functional
group(s) was (were) NOT synthesized in the first semester (as described in the text)?
e) Which functional group has the most electron rich sp2 oxygen? Provide a structure
to support your answer. Resonance comes in handy here….
f) Is a Bronsted acid a nucleophile or electrophile? A Bronsted base?
g) How many atoms are sp2 hybridized in acetic acid?
h) How many atoms are sp2 hybridized in phenol?
i) How many atoms are sp2 hybridized in heroin?
3. Structural Relationships and Language - Review all terms and definitions for the following:
Constitutional isomers vs Conformation isomers vs Configurational Isomers
Stereoisomers (Diastereomers, Enantiomers)
Optical Activity, Racemic, Meso
Determination of Absolute Configuration
Questions:
a) What term can be used to describe the isomeric relationship above?
b) Each molecule above can be described as a vicinal diol. What is a more common and
more utilized term for describing a vicinal diol (Hint: It is often used in common
nomenclature and can be found on the Functional Group List on page .
I use this lab sequence over a couple of lessons to get to grips with some basics of different types of reactions, balancing, writing formulas and problem-solving.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
How to Create Map Views in the Odoo 17 ERPCeline George
The map views are useful for providing a geographical representation of data. They allow users to visualize and analyze the data in a more intuitive manner.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
2. 2 Assessor’s
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You are advised to spend 60 minutes answering the questions in this booklet.
QUESTION ONE: IONIC COMPOUNDS
(a) Magnesium and calcium atoms both form ions with a charge of +2. Magnesium atoms form
Mg2+ ions, and calcium atoms form Ca2+ ions.
Explain why magnesium and calcium atoms form ions with the same charge of +2. In your
answer, you should:
• define an ion
• explain why atoms form ions
• identify the group on the periodic table where the two atoms are found
• explain why both magnesium and calcium ions have a charge of +2.
(b) Sodium and beryllium atoms form ions with different charges.
Complete the table below.
Periodic table Electron arrangement Charge on the ion that
Element
group number of atom the atom forms
Sodium
Beryllium
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(c) Explain why the ions in sodium hydroxide combine to give the formula NaOH but the ions in
beryllium hydroxide combine to give the formula Be(OH)2.
In your answer, you should:
• compare the charges on the individual ions found in the compounds sodium hydroxide and
beryllium hydroxide
• explain why the ions combine in the ratios the way they do to form the compounds NaOH
and Be(OH)2.
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QUESTION TWO: ISOTOPES AND IONS
6
Lithium atoms can exist in different forms called isotopes. Two of these isotopes are Lithium-6 ( 3
7
Li ) and Lithium-7 ( 3 Li).
6 7
(a) Explain why 3 Li and 3 Li are both neutral atoms. In your answer, you should fully
describe their atomic structure and state their electron configuration.
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7
(b) Berylium can exist as an isotope in the form of beryllium-7 ( 4 Be).
7 6 7
Discuss how the mass of 4 Be compares with 3 Li AND 3 Li. In your answer, you
should:
• consider the atomic structure of each atom
• consider the meaning of the numbers ‘6’ and ‘7’ in terms of the atomic structures
• explain how the particles within an atom contribute to its overall mass.
You may draw labelled diagrams in the box below to support your answer.
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QUESTION THREE: ACID AND BASE REACTIONS
A student puts 5 mL of dilute hydrochloric acid into a boiling tube and adds five drops of universal
indicator to the solution. The student then takes a solution of sodium hydroxide of the same
concentration as the acid and adds it one drop at a time to the acid until the colour stops changing.
(a) (i) Describe the colour of the universal indicator solution:
• in the hydrochloric acid before any sodium hydroxide was added.
• when the sodium hydroxide was added and the colour of the solution stopped
changing.
(ii) As the sodium hydroxide is added several colour changes occur.
Explain how the colour changes relate to pH AND what ions are present in the solution
colour changes.
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(b) The student combines equal volumes of nitric acid solution and sodium carbonate solution.
Both solutions have the same concentration.
Discuss what happens in this reaction. In your answer, you should:
• name the type of reaction involved and the ions involved
• describe what the student would observe
• state the products of the reaction and link these to the observations made
• write a word equation for the reaction
• write a balanced symbol equation for the reaction.
Word equation:
Balanced symbol equation:
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QUESTION FOUR: RATES OF REACTION
Marble chips (calcium carbonate) are added to dilute hydrochloric acid in a conical flask. The flask
is connected to an inverted measuring cylinder in a trough of water, as shown in the diagram below.
The volume of gas produced is measured over a few minutes, and the results used to sketch a graph.
(a) The slope of the graph is steep at the beginning and then levels off over time.
Explain what is happening, in terms of particles, during the reaction.
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(c) Complete the word and symbol equations below to show the reaction in the experiment.
Word equation:
Balanced symbol equation:
(d) The experiment is repeated but this time the same mass of marble chips is crushed into a
powder before it is added to the flask.
Discuss the effect on the reaction rate of using powdered marble with hydrochloric acid
compared with using marble chips. In your answer, you should:
• compare the rates of reaction
• explain the differences in the reaction rate by discussing how crushing the marble chips
affects the number of particle collisions.
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Extra paper for continuing your answers, if required.
Clearly number the question.
Question
number
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12. 12 Assessor’s
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Extra paper for continuing your answers, if required.
Clearly number the question.
Question
number
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