Notes, abstracts, papers, exams and problems of Chemistry

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Properties of gases(diffusion and pressure)

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Chem Cheat Sheet

Mol = M*L

m = mol/Kg

Strong Acids

HCL hydrochloric

H2SO4 sulfuric

HNO3 nitric

HBR hydrobromic

HI hydroiodic

HCLO4 perchloric

Cp H2O (l) = 4.184

Cp H2O (s) = 2.03

Cp H2O (g) = 1.998

ΔHfusion of H20 = 6.02

ΔHvap of H20 = 40.7

Real gases do have attractive forces at __________ temperatures:low

2.Ideal gases do not have attractive forces at _______ tempersatures:high

3.Real gases are not always far apart at ______temperatures:high

4.Ideal gases are far apart at _______ temperatures:low

5.An amorphous solid still has all the properties of a solid except for

 its ___________ _______________:disorganized arrangement

6.ΔH fusion of H2O:6.02

7.ΔH vaporization of H2O:40.7

8.Equation for solving phase changes (Ex. If you had 100g of liquid

water at 100

... Continue reading "Properties of gases(diffusion and pressure)" »

Àcid hiposulfuroso

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Acids+MetalOxide>Salt+Water
Acid+Metalhydroxide>salt+water
acid+metalcarbonate>sal+water+carbondioxide
PH:1)13 2)1.4 3)25cm3
Copper sulphate crystals
Add black copper oxide in excess so you know
all the acid has reacted. Filter to remoce the excess copper oxide and obtain a puré solution of the soluble salt. Heat the solution until crystals form on a glass rod dipped into it. Then leave to cool slowly so that the crystals form. Different salta. Base has to be insoluble in water and the salt formed has to be soluble eg: mgcarbonate *hydrochloric acid>mgcloride

vocabulary

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enlarge, frame(marc), hang(penjar), print,save to hard drive, take//artist, brush, bust, easel(cavallete), gallery, model, paint, palette, pedestal, portfolio, sculptor, sculpture// make a choice, a commitment, an announcement, an impact, the grade// do a part-time job, someone a favour, your best//extended family, bride(novia), groom(novio), teammates, partner(socio), best man, bridesmaid(dama), colleagues, relative(familiar), nuclear family, parents// leader, introvert, ally(aliado), extrovert, follower, enemy//time travel, microwave, android, solar-powered car, black hole, precognition, mp3 player, relativity, smartphone, the Big Bang//astronomy, biology, botany, chemistry, geology, mathematics, medicine, meteorology, physics, zoology

Molecules i àtoms

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1. Match the symbol on the left with its appropriate description on the right. 
d →               (a) A precipitate forms. 
a ↓                 (b) A gas forms. 
b ↑                (c) A reversible reaction occurs.
f (l)                (d) Heat is applied to the reactants. 
e (aq)            (e) A chemical is dissolved in water. 
c ←→            (f ) A chemical is in the liquid state. 

3. In each of the following formulas, write the total number of atoms present. 
12 atoms                  a. 4SO>2 
6 atoms                    b. 8O>2 
51 atoms                  c. 3Al>2(SO4)>3 
3x10^24 atoms        d. 6x10^23 HNO3 

1. Match the equation type on the
... Continue reading "Molecules i àtoms" »

Last Chem Test

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acid: proton donor; produces hydronium ions in aqueous solution

base: proton acceptor; produces hydroxide ions in aqueous solution
conjugated acids: acid that forms when a base gains a proton
conjugated base: base that forms when an acid loses a proton
neutralization: reaction where an acid and a base react to produce a salt and water
-acids: taste sour, tart, sharp; stinging sensation to skin; corrosive; changes blue to red; conduct electricity
-base: bitter taste; slippery feel; dissolve easy in water; change red to blue; neutralize properties of acids.

NaNO3=salt Ba(OH)2=base H2SO4=acid NH4OH=base HBr=acid FeBr3=salt 
pH from 8-14= base pH from 0-6= acid

Consider an atom that has an atomic number of 8 and a mass number of 17 If it has a -2 charge it contains electrons.

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-Explain What- A pure substance is a sample of matter with both definite and constant Composition with distinct chemical properties. Every pure element is a Substance. Every pure compound is a substance.Ex: water.

- What is- . A solution is a combination of two things, but it is well mixed down to the Molecular level and stable.Ex:Salt water .A heterogeneous mixture on the other Hand will settle.Ex:Chocolate milk.

 -what does- The chemical formula of a compound Indicates what the compound is made of. For example H2O has two hydrogen and One oxygen.

-Explain How- Atoms of different elements have different numbers of protons and neutrons In their nucleus. More importantly, they have different numbers of electrons Around the nucleus. It is the

... Continue reading "Consider an atom that has an atomic number of 8 and a mass number of 17 If it has a -2 charge it contains electrons." »

Our body takes its energy from:

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My renewable solar energy is solar and it comes from the sun that is converted into thermal or electrical energy. In the basque country we use only 1,8% of all the amount of energy, because its very expensive and takes a lot of space. Solar energy can work in three different ways: the solar cells absorb the sunlight and makes the solar energy into electric energy, another is the solar water heating: the sun heats the water with the glass panels and they don´t use so much gas or electricity to heat the house, and the last one is that a large amount of mirrors concentrate all the heat in a small space and it produces very high tenperatures. Solar energy was created in the 7 century B.C. To today. They started to concentrate the sunlight to
... Continue reading "Our body takes its energy from:" »

Rotation dollars sales and profit

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Exercise 3 – Analyzing financially the possible changes In price or volume

Apple iPhone sales in 2014 were around 150 000 000 Units with the price of 640 USD per unit. In 2015 Apple wants to introduce New model in its iPhone series. Following is the company's average costs to Manufacture one unit of iPhone (see table 1).

Table 1 – One unit iPhone Manufacturing Cost Estimates

Flash Memory & RAM

20.85 USD

Display & Touchscreen

44.00 USD

Processor

17.50 USD

Sensors

6.50 USD

Cameras

18.00 USD

Cellular Radio

34.00 USD

Wireless Radio

5.00 USD

Battery

4.50 USD

Power Management

8.50 USD

Mechanical Parts

33.00 USD

Packaging

7.00 USD

Production

8.00 USD

Licensing Fees

20.00 USD

Source: http://www.Digitaltrends.Com/mobile/iphone-cost-what-apple-is-paying/

In table 2 there... Continue reading "Rotation dollars sales and profit" »

Que es motion gravity friction force work

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t: A strong acid is one that will completely ionize

f: When blue litmus paper is placed in a weak acid, it will turn a darker shade of blue
f: When ph paper provides a reading which says it has a ph of 9, the substance is considered a weak acid.
f: Alpha, Beta, and Gamma are all forms of nuclear radiation that contain either positive of neg charges.
t: Fission is the process where a large nucleus splits unto two smaller nuclei.
f: The most common isotope of carbon that is used for radioactive dating is carbon-13.
t: Static friction is friction that occurs when an object is not moving.
f: When an object is accelerating but it is not traveling in a straight line, it must be moving vertically.
t: Friction is force that always opposes the motion of an
... Continue reading "Que es motion gravity friction force work" »

Particles transcision

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Intermediates: species that appear in some steps but not in the net equation

Activated complex-transitional structure that results from an effective collision and that persists while old bonds are breaking and new ones are forming. Activated complex is very short lived molecular complex in which bonds are in the process of being broken and formed

6 factors that affect reaction:

1. Natrue of reactants

2. Concentration of reactants-can only be increased for gases or aqueous solutions-higher concentration faste rreaction

3. Temperature, increase in t, increase in reaction rate bc particles have a higher KE at a higher T and collide more often. Greater fraction of particles have sufficient ke to react, 10c rise in T doubles reaction rate.

4. Catalyst... Continue reading "Particles transcision" »