chemistry
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Michael L. Bishop, Edward P. Fody, Carleen Van Siclen • ISBN 9781284238860
Karen C. Timberlake • ISBN 9780134421353
Carl A. Burtis, David E. Bruns • ISBN 9781455741656
David Shubert, PhD, John Leyba, PhD, Sharon Niemann, DNAP, CRNA • ISBN 9780826107831
Julia Burdge • ISBN 9781260565850
Latest notes & summaries chemistry
Explain why the first ionisation energy of barium is less than the first ionisation energy of calcium - 
Ans .-more (electron) shells / (outer) electrons further from the nucleus / larger atoms / more 
shielding 
-so weaker attraction of nucleus/protons for (outer) electrons 
Magnesium reacts readily with steam. 
State two observations you would make when magnesium reacts with steam. Write an equation for the 
reaction - Ans .White solid / white ash 
Bright light / white light Mg + H2OMgO + H2...
1. The melting point of XeF4 is higher than the melting point of PF3 
Explain why the melting points of these two compounds are different 
In your answer you should give the shape of each molecule, explain why each molecule has that shape 
and how the shape influences the forces that effect the melting point (6) - Ans .- Xe has 8 electrons in 
its outer shell, giving XeF4 4 bonding pairs of electrons and 2 lone pairs. 
- Electron pairs repel as far as possible, lone pairs repel even further ...
A student prepares a solution of calcium nitrate by reacting dilute nitric acid, HNO3, with the base 
calcium hydroxide, Ca(OH)2. 
(i) Why is calcium nitrate an example of a salt? - Ans .The H+ ion in a nitric acid has been replaced by 
a 
metal ion OR by a Ca2+ ion 
MCl2.2H2O is a salt with water of crystallisation, and M is a metal. the water of crystallisation makes up 
22.2% by mass of the hydrated salt. What is the relative formula mass of the anhydrous salt? - Ans 
.126 
Strontium react...
What is the aim of this practical? 
To determine the enthalpy change of reaction by Hess' Law based on experimental evidence. This will 
involve measuring the temperature changes in the reactions of both K₂CO₃ and KHCO₃ with hydrochloric 
acid and applying your knowledge of Hess' Law to calculate the enthalpy change of thermal 
decomposition of KHCO₃. 
What is enthalpy change of reaction? 
The enthalpy change associated with a stated equation. 
What chemicals are used in this practi...
▪ Relative atomic mass - Ans .The weighted mean mass of an atom of an element compared 
with one-twelfth of the mass of an atom of carbon-12. 
▪ Relative isotopic mass - Ans .The mass of an atom of an isotope compared with one-twelfth 
of the mass of an atom of carbon-12. 
▪ empirical formula - Ans .The simplest whole number ratio of atoms of each element present 
in a compound 
▪ molecular formula - Ans .A chemical formula that shows the number and kinds of atoms in a 
molecule, but...
Silver nitrate+ nitric acid + chloride ions - Ans .White precipitate 
 Silver nitrate+ nitric acid + bromide ions - Ans .Cream precipitate 
 Silver nitrate+ nitric acid + iodide ions - Ans .Yellow precipitate 
 Substances that decolorise bromine water - Ans .Alkenes 
 Electrophiles - Ans .Electron pair acceptors, attracted to electrons e.g H+ 
 NaF and NaCl - Ans .Produces misty fumes with conc sulphuric acid 
 NaBr - Ans .Produces misty and orange/brown fumes with conc sulphuric acid 
 NaI - A...
Introduction. 
· The iron tablet contains: spray dried liquid glucose, stearic acid, magnesium stearate, microcrystalline 
cellulose, lactose granules containing lactose, maize starch and pregelatinized maize starch, gelatin, 
sucrose and titanium dioxide. 
· Iron is an essential element in blood production and is found in the haemoglobin and muscle cells 
called myoglobin. Irons role includes helping to form and oxygenate our blood cells and haemoglobin, 
helps to convert food to energy, ...
▪ Proton - Ans .A subatomic particle that has a positive charge and that is found in the nucleus 
of an atom 
▪ neutron - Ans .A subatomic particle that has no charge and that is found in the nucleus of an 
atom 
▪ electron - Ans .A subatomic particle that has a negative charge 
▪ atom - Ans .consists of a nucleus with protons and neutrons, that is surrounded by electrons 
▪ isotopes - Ans . 
▪ mass number - Ans .A - the sum of protons and neutrons in a nucleus of an atom 
▪ atom...
Covalent bond - Ans .A chemical bond that involves sharing a pair of electrons between atoms in a 
molecule, the positive nuclei attracts the negative charge of the bonding pair of electrons 
Bonding pair - Ans .a pair of electrons shared between two atoms 
Metallic bonding - Ans .a bond formed by the attraction between positively charged metal ions and 
the delocalised electrons around them 
Ionic bonding - Ans .the electrostatic attraction between the cation and the anion hold the 
compound...
General Chemistry 1 Questions & Answers 
1 atm in mmHg - CORRECT ANSWER- 760 mmHg 
accuracy - CORRECT ANSWER- A description of how close a measurement is to the true 
value of the quantity measured. 
Acetic acid - CORRECT ANSWER- HC2H3O2; weak acid 
acid ionization - CORRECT ANSWER- reaction of an acid with water 
actual yield - CORRECT ANSWER- the measured amount of a product obtained from a 
reaction 
Ammonia - CORRECT ANSWER- NH3 (weak base) 
amount of substance prefix - CORRECT ANSWER- mol (...