Welcome, Guest: Register On Nairaland / LOGIN! / Trending / Recent / New
Stats: 3,151,601 members, 7,812,967 topics. Date: Tuesday, 30 April 2024 at 12:16 AM

Nairaland Jamb Tutorial Centre {chemistry Thread} - Education (3) - Nairaland

Nairaland Forum / Nairaland / General / Education / Nairaland Jamb Tutorial Centre {chemistry Thread} (25913 Views)

2016 NAIRALAND JAMB TUTORIAL {the Physics Thread } / Nairaland 2016 Jamb Tutorial Classroom [chemistry Thread] / Nairaland Jamb Tutorial Centre. {NJTC} (2) (3) (4)

(1) (2) (3) (4) (5) (6) (7) (8) (9) (Reply) (Go Down)

Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by kuderrich: 11:26pm On Dec 02, 2014
Pls submit your answers to the class work on or b4 11am tomorrow. Thankz
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by Nobody: 12:37am On Dec 03, 2014
kuderrich:
Pls submit your answers to the class work on or b4 11am tomorrow. Thankz
1. distillation
2. precipitation (not sure tho)
3. crude oil is made up of liquids which have different boiling points, thus making fractional distillation the suitable separating technique
4. (i) compounds are hardly separated with new substances being formed, while mixtures are easily separated with no new substance being formed
(ii) compounds are products of chemical change while mixtures are products of physical change
5. (a)Bronze
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by Kunlexic(m): 5:34am On Dec 03, 2014
kuderrich:
SEPARATING FUNNEL:
A mixture of Petrol and Water do not mix together to form a single liquid, b’cos they are non-polar and polar solvent respectively. They rather separate out into two distinct layers when they are added. A separating funnel is useful here; d lower denser liquid layer is tapped off, leaving d upper less dense layer in d funnel.

CHROMATOGRAPHY
Chromatography uses a solvent moving over a porous absorbent medium (e.g paper or gel) to separate a solute. They are widely used to separate coloured as well as colourless substance
******************


QUESTIONS
1.A mixture of kerosene and diesel oil can be separated by.............
2. A mixture of Naphthalene and Candle will be separated by..........
3. What property is used in choosing Fractional distillation as a separating technique for a mixture of fractions of crude oil?
4. Mention 2 differences between compound and mixture?
5. Which of the following is a mixture (a) Bronze (b) Ethanol (c) CO2

1. Separating funnel
2. Sublimation
3.Boiling points
4.(i) compounds are always homogeneous. While mixture can be homogeneous. o, r heterogeneous.
(ii) the constituents that make up a matter cannot retain their individual properties while constituents of mixtures retain their properties
5.Bronze(mixture of copper and tin)
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by Halpher(m): 9:19am On Dec 03, 2014
kuderrich:
SEPARATING FUNNEL:
A mixture of Petrol and Water do not mix together to form a single liquid, b’cos they are non-polar and polar solvent respectively. They rather separate out into two distinct layers when they are added. A separating funnel is useful here; d lower denser liquid layer is tapped off, leaving d upper less dense layer in d funnel.

CHROMATOGRAPHY
Chromatography uses a solvent moving over a porous absorbent medium (e.g paper or gel) to separate a solute. They are widely used to separate coloured as well as colourless substance
******************


QUESTIONS
1.A mixture of kerosene and diesel oil can be separated by.............
2. A mixture of Naphthalene and Candle will be separated by..........
3. What property is used in choosing Fractional distillation as a separating technique for a mixture of fractions of crude oil?
4. Mention 2 differences between compound and mixture?
5. Which of the following is a mixture (a) Bronze (b) Ethanol (c) CO2


Well ntin much.

1.Separting funnel teqnique(immicible liquids)

2.A. Sublimation B.Evaporation to dryness.
I.E derivatives of Benzene
(Aromatic hydrocarbon are commonly sublime)

3.Diff in boilling point of 10' > btw them.

4.
A. Chemically combine / physically combine
B.Cannot easily be saparated by physical means/can easily be saparated by physical means..etc

5.Bronze.(An Alloy)
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 8:30pm On Dec 03, 2014
Having checked d response we av so far, I 'll give d answers succinctly and then u can mark urself right or wrong.

1. Distillation (they are immiscible liquids)

2. Sublimation

3.Differences in their boiling points.

4. Compound can be written by a chemical formula while mixture cannot;
Mixture is associated with physical change while compound is associated with a chemical change
Constituents in mixture can be added in any ratio by mass, while constituents is present in fixed ration by mass for compound


5. Bronze.


To everyone that attempted the questions, halpher, kunlexic, preboy, bolaji3071, victar...I commend your efforts and I wanna say be encouraged. Be encouraged to do more, ask questions if you av to, solve questions, be positive, be optimistic, set a goal and work towards it.

There will be other aspect that will be more difficult, prepare ur mind for it, chemistry cannot intimidate you, and you are not d first person to learn chemistry, others have learnt it and passed it excellently well, yours will not be different.

Goodluck....Adebayour26
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by Nobody: 9:42pm On Dec 03, 2014
4/5... Not bad bt I've gotta do better.
Big ups to our tutors kuderrick and adebayour26, you guys rock!!... Looking forward to the next topic
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 5:33am On Dec 04, 2014
Preboy:
4/5... Not bad bt I've gotta do better.
Big ups to our tutors kuderrick and adebayour26, you guys rock!!... Looking forward to the next topic
Our next topic should be [Kinetic Theory of gases.
You can do well to read ahead, and be fully prepared.
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 5:38am On Dec 04, 2014
Dsd1pumpking:

Wow, this is so great. But ,is there a whatsapp group to join to make it more easier to ask,read,answer questions AFAP? Plz help us create one
If most people are interested and if it will helo, we will work on creating one.
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by Dsd1pumpking(m): 6:29am On Dec 04, 2014
adebayour26:

If most people are interested and if it will helo, we will work on creating one.
We give u the ultimate support and plz, do inform us if it is succesfully created
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 3:11pm On Dec 04, 2014
Dsd1pumpking:

We give u the ultimate support and plz, do inform us if it is succesfully created
Then drop ur whatsapp number, for privacy send it to our email....I mean myself or Kudderich
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by bolaji3071(m): 9:50pm On Dec 04, 2014
adebayour26:

Then drop ur whatsapp number, for privacy send it to our email....I mean myself or Kudderich

SIR. Ur email address please.
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by Dsd1pumpking(m): 11:34pm On Dec 04, 2014
adebayour26:

Then drop ur whatsapp number, for privacy send it to our email....I mean myself or Kudderich
08132139682
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 6:55am On Dec 05, 2014
bolaji3071:


SIR. Ur email address please.
adebayour26@gmail.com
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 9:05am On Dec 05, 2014
The whatsapp group has been created already, so we are expecting your phone numbers in d mail.
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by kuderrich: 11:02am On Dec 05, 2014
It feels good being back to class, so sorry i was unable to update yesterday, was kinda busy.

ATOMS, MOLES, FORMULAE AND. EQUATIONS.

Matter is made up of discrete particles, the main ones being atoms, molecule and ions.

ATOMS
The word atom was first used by ancient greek which means indivisible, to describe the smallest particle of any substance. It actual existence was not established until the 19th century when an English chemist (John Dalton) put forward a theory to describe the nature of atom. Atom is now considered the basic unit of simple substances or element.
What is an atom? An atom is the smallest indivisible particle of an element which can part in a chemical reaction or a smallest part of an element that can ever exist and still possess the chemical properties of that element.

MOLECULE
Most atoms cannot exist alone. They generally bond with other atoms to form molecules. Molecules may be made-up of atoms of the same element or of different elements. The number of atoms in each molecule of an element is called ATOMICITY. The number atoms in the molecule of a compound may be small or large.
What is a molecule? A molecule is the smallest particle of a substance that can normally exist alone and still retain the chemical properties of that substance, be it an element or a compound.

IONS
Some substance are not built up of atoms or molecules, but are made up of charged particles called ions. There are two types of ions; the positively charged ions or CATIONS and the negatively charged ions or ANIONS. An ionic substance has the same number positive and negative ions, so that it is electrically neutral.
What is an ion? An ion is any atom or group of atoms which possesses an electric charge.

DALTON’S ATOMIC THEORY
In 1808, John Dalton proposed the atomic theory which can be summarised as follows:
(1) All elements are made up of small, indivisible particle called atoms.
(2) Atoms can neither be created nor destroyed.
(3) Atoms of the same element are alike in every aspect, and differ from atoms of all other elements.
(4) When atoms combine with other atoms, they do so in simple ratios.
(5) All chemical changes result from the combination or the separation of atoms.
The atomic theory was partially supported by experimental evidences deduced from the law of conservation of mass, the law of definite proportions etc it could not explain electrolysis and certain other phenomena. As a result of new discovery Dalton’s original atomic theory has undergone several modifications but the principal aspects as outlined above are still useful in the study chemistry.
You must have been familiar with some elements and their symbols, so we’ll have to jump it and move to some other aspects.

RELATIVE ATOMIC MASS
Early scientist expressed the mass of atoms as a ratio by comparing the mass of one atom of any element with the mass of hydrogen atom, the lightest known atom. The relative atomic mass carries no units. It’s only a ratio.
Relative atomic mass, A of an element is the number of times the average mass of one atom of that element is heavier than one twelfth the mass of one atom of carbon-12

RELATIVE MOLECULAR MASS
Every molecule must have a mass or molecular mass, since it composed of atoms the mass of molecule is very small; it is also expressed as a ratio of the carbon-12.
The relative molecular mass, M of an element or a compound is the number of times the average mass of one molecule of it is heavier than one-twelfth the mass of one atom of carbon-12. N:B the relative molecular mass, M of an element or compound is the sum of the relative atomic masses of all the atoms in one molecule of that substance.
Example: calculate the relative molecular mass of sodium trioxocarbonate (IV) Na2CO3. (Na = 23, C = 12, O = 16).
Solution: one molecule of Na2CO3 has 2Na, 1C and 3O atoms
= 2 x At of Na + 1 x At of C + 3 x At of O
= (2 x 23 + 1x 12 + 3 x 16)
= 46 + 12 + 48
=106.
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 11:33am On Dec 05, 2014
So we can illustrate that Atomic number and Atomic mass are like a set of boys arranged serially, their individual serial number (1,2,3,4, 5,6,7.....) is d atomic number and their weight (like 50kg, 65kg,71kg, 80kg.....) is the Atomic mass.

2 Likes

Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by bolaji3071(m): 12:34pm On Dec 05, 2014
following.
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by Akerry(m): 12:58pm On Dec 05, 2014
adebayour26:

If most people are interested and if it will helo, we will work on creating one.
now that the Whatsapp group has been created, what will happen to this thread? 08070922921 is my number, add me
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 6:37pm On Dec 05, 2014
Akerry:
now that the Whatsapp group has been created, what will happen to this thread? 08070922921 is my number, add me
Trust me, we understand that not everybody is registered on whatsapp, so this group is still active.

However, no teaching is done on whatsapp but interactions and enquiry. All classes & teaching continues to hold here on Nairaland.

Thanks.
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by Akerry(m): 9:28pm On Dec 05, 2014
adebayour26:

Trust me, we understand that not everybody is registered on whatsapp, so this group is still active.

However, no teaching is done on whatsapp but interactions and enquiry. All classes & teaching continues to hold here on Nairaland.

Thanks.
nice one....God bless you.. Seriously following this thread....though i am not a jambitogrin God bless u once again
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by fedcom(m): 10:25pm On Dec 06, 2014
Example: calculate the relative molecular mass of sodium trioxocarbonate (IV) Na2CO3. (Na = 23, C = 12, O = 16).
Solution: one molecule of Na2CO3 has 2Na, 1C and 3O atoms
= 2 x At of Na + 1 x At of C + 3 x At of O
= (2 x 23 + 1x 12 + 3 x 16)
= 46 + 12 + 48
=106.



[/quote]
OP pls i dont understand were the 30 atoms came in
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by mathefaro(m): 6:01pm On Dec 07, 2014
fedcom:
Example: calculate the relative molecular mass of sodium trioxocarbonate (IV) Na2CO3. (Na = 23, C = 12, O = 16).
Solution: one molecule of Na2CO3 has 2Na, 1C and 3O atoms
= 2 x At of Na + 1 x At of C + 3 x At of O
= (2 x 23 + 1x 12 + 3 x 16)
= 46 + 12 + 48
=106.




OP pls i dont understand were the 30 atoms came in
it's not 30 but 3 O, which means 3 oxygen atoms
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 11:02pm On Dec 07, 2014
mathefaro:
it's not 30 but 3 O, which means 3 oxygen atoms
Thanks for d correction.
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by mathefaro(m): 12:24am On Dec 08, 2014
adebayour26:

Thanks for d correction.
you're welcome
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 9:29am On Dec 10, 2014
It's a Beautiful wednesday morning and I wanna apologise on behalf of Kudderich and myself for being away for awhile, we promise to make it up in a lot of ways.

From the last class, we learnt d basics, atoms, relative atomic mass and d likes.
Class continues today.

PLEASE STAY WITH US

1 Like

Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 9:36am On Dec 10, 2014
MOLE

Chemical reactions take place between individual particles such as atoms, molecules & ions of d reacting substance e.g
A + B -------> C
An equal number of particles of A & B are always needed to yield a definite number of particles of C.
One mole of a substance is d amount containing as many elementary entities as d number of atoms in exactly 12gram of Carbon-12.
The unit is mol

It was found that one mole contain 6.02x10²³ atoms. The number is known as Avogadro number.
For instance, 1 dozen of eggs means 12 eggs, so also 1 mole of a substance contains 6.02x10²³ representative particles of that substance. Such representative particles may be atoms, molecules or ions.

No of moles= No of particles/6.02x10²³


Example 1:
How many moles of Magbesium is 3.20x10²² atoms of Magnesium?

Solution
Using the formula above, d number of particles is 3.10x10²² and mole is d unknown
i.e d conversion is from atoms---> moles.

No of moles= (3.10x10²²)/(6.02x10²³)
=0.05mol of Mg.


To calculate d number of MOLE itself, apply this simple formula:

Mole= mass/molar mass

Unit of molar mass is g/mol

Note that there must be consistency in d units being used
For d calculation of mole, mass in gram/molar mass in g/mol.
the two gram will cancel out, thereby leaving out mol as d unit of MOLE

1 Like

Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by sorbentcrooner(m): 12:07pm On Dec 14, 2014
Hello thread, pls how can u distinguish between a non-terminal alkyne and an alkene?
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 7:43pm On Dec 16, 2014
1. What is first Ionization energy?

How does it affect down d group and across the period?

2. Define Isotope.

3. A solid Chloride E which sublimed on heating reacted with an alkali F to give a choking gas G. G turned moist red litmus paper blue.
Identify E, F & G
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by Kunlexic(m): 11:18pm On Dec 16, 2014
adebayour26:
1. What is first Ionization energy?

How does it affect down d group and across the period?

2. Define Isotope.

3. A solid Chloride E which sublimed on heating reacted with an alkali F to give a choking gas G. G turned moist red litmus paper blue.
Identify E, F & G

1.This is the energy required to remove the most loosely bounded electrons from one mole of an atom in the ground states.
M------>M^+ +e^-

2.Isotopes are atoms of the same elements that have the same atomic number but different mass numbers as a result of differences in number of neutrons in the nuclei of each atom.

3.E-ammonium chloride
F-NaOH solution
G-ammonia
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 5:21am On Dec 17, 2014
Kunlexic:


1.This is the energy required to remove the most loosely bounded electrons from one mole of an atom in the ground states.
M------>M^+ +e^-

2.Isotopes are atoms of the same elements that have the same atomic number but different mass numbers as a result of differences in number of neutrons in the nuclei of each atom.

3.E-ammonium chloride
F-NaOH solution
G-ammonia

PERFECT.

So What's d trend of ionisation energy down d group and across d period?
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by Kunlexic(m): 6:57am On Dec 17, 2014
adebayour26:


PERFECT.

So What's d trend of ionisation energy down d group and across d period?
down the group,ionisation energy decreasea and it increases across the period
Re: Nairaland Jamb Tutorial Centre {chemistry Thread} by adebayour26: 7:04am On Dec 17, 2014
Kunlexic:
down the group,ionisation energy decreasea and it increases across the period
CORRECT

(1) (2) (3) (4) (5) (6) (7) (8) (9) (Reply)

Handsome Nigerian, Onuaha Bags A Gold Honor As An INTERN In L.W CHIROPRACTIC,USA / UNIZIK Reacts After Facebook User Advertised Its Admission Slots For Sale / JAMB Official Makes U-turn, Says N36m ‘collected By Superior’ — NOT Snake

(Go Up)

Sections: politics (1) business autos (1) jobs (1) career education (1) romance computers phones travel sports fashion health
religion celebs tv-movies music-radio literature webmasters programming techmarket

Links: (1) (2) (3) (4) (5) (6) (7) (8) (9) (10)

Nairaland - Copyright © 2005 - 2024 Oluwaseun Osewa. All rights reserved. See How To Advertise. 53
Disclaimer: Every Nairaland member is solely responsible for anything that he/she posts or uploads on Nairaland.