<![CDATA[Chemistry Trivia (Q&amp;A and some tips and tricks)]]>Pls help.

1. When copper ions are reduced to copper, correct if put ‘Copper is reduced.’?
2. For reaction between zinc and acid in excess, correct if put ‘The initial rate of reaction is the highest because the mass of zinc is the greatest.’
TIA

]]>https://forum.kiasuparents.com/topic/95661/chemistry-trivia-q-amp-a-and-some-tips-and-tricksRSS for NodeSat, 18 Apr 2026 09:42:06 GMTThu, 07 Oct 2021 00:20:29 GMT60<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Sun, 07 Jun 2020 05:08:49 GMT]]>Hi,


What is the proper calculation for the percentage purity of a substance?
Thanks for your help.

]]>https://forum.kiasuparents.com/post/1979849https://forum.kiasuparents.com/post/1979849Sun, 07 Jun 2020 05:08:49 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Tue, 02 Jun 2020 09:11:31 GMT]]>

chaocheng12\" post_id=\"1978992\" time=\"1591012814\" user_id=\"185205:

leeh40\" post_id=\"1978968\" time=\"1591004063\" user_id=\"185343:

Hi,

Just a random question...how are these so-called greenhouse gases cause global warming? Is there a chemical reaction taking place?

Earth’s atmosphere works something like a giant glass greenhouse. As the sun’s rays enter our atmosphere, most continue right down to the planet’s surface. As they hit the soil and surface waters, those rays release much of their energy as heat. Some of the heat then radiates back out into space. However, certain gases in our atmosphere, such as carbon dioxide, methane and water vapor, work like a blanket to retain much of that heat. This helps to warm our atmosphere. The gases do this by absorbing the heat and radiating it back to Earth’s surface. These gases are nicknamed “greenhouse gases” because of their heat-trapping effect. The increase in the levels of these greenhouse gases due to our contributions such as burning of fossil fuels and deforesting gives rise to its effect to global warming.

So, yes there is still Chemistry in it's process.

great job and a perfect question! to add, here are the chemical reaction of the biological processes which gives off greenhouse gases,

combustion of fossil fuel: 6 O2 + C6H12O6 --------> 6 H2O + 6 CO2 + energy

methanogenesis, or the methane production - usually occurs in fresh water wetlands:
CH3COOH --------> CO2 + CH4.

NATURALLY OCCURRING or those made by humans,

chlorofluorocarbons - (anthropogenic) created by humans, since no natural known source of greenhouse gas which contains chlorine, fluorine and carbon

nitrous oxide (N2O) - by product of nitrification and denitrification or are biotically transformed by microbes; possible source is fertilizer on agricultural fields.

troposhepric ozone (O3) - a constituent of smog; can be produces from other greenhouse gases by,
- CH4 + 4O2 --------> HCHO + H2O + 2O3
- NO2 + O2 <--------> NO + O3


Thanks lee, chaocheng and change146!

]]>https://forum.kiasuparents.com/post/1979099https://forum.kiasuparents.com/post/1979099Tue, 02 Jun 2020 09:11:31 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Tue, 02 Jun 2020 08:51:29 GMT]]>

wooyin08\" post_id=\"1979009\" time=\"1591017023\" user_id=\"185522:

Hello, I'm in SEC btw. Thanks!
Hi wooyin,

please check your inbox.

Thanks,
UPTAS

]]>https://forum.kiasuparents.com/post/1979095https://forum.kiasuparents.com/post/1979095Tue, 02 Jun 2020 08:51:29 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Mon, 01 Jun 2020 13:14:58 GMT]]>

leeh40\" post_id=\"1978968\" time=\"1591004063\" user_id=\"185343:

Hi,

Just a random question...how are these so-called greenhouse gases cause global warming? Is there a chemical reaction taking place?
Yes, agree with the other answer. These gases give a blanket effect trapping heat. So, the earth's temperature increases which leada to global warming.

]]>https://forum.kiasuparents.com/post/1979010https://forum.kiasuparents.com/post/1979010Mon, 01 Jun 2020 13:14:58 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Mon, 01 Jun 2020 13:10:23 GMT]]>Hello, I’m in SEC btw. Thanks!

]]>https://forum.kiasuparents.com/post/1979009https://forum.kiasuparents.com/post/1979009Mon, 01 Jun 2020 13:10:23 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Mon, 01 Jun 2020 12:00:14 GMT]]>

leeh40\" post_id=\"1978968\" time=\"1591004063\" user_id=\"185343:

Hi,

Just a random question...how are these so-called greenhouse gases cause global warming? Is there a chemical reaction taking place?
Earth’s atmosphere works something like a giant glass greenhouse. As the sun’s rays enter our atmosphere, most continue right down to the planet’s surface. As they hit the soil and surface waters, those rays release much of their energy as heat. Some of the heat then radiates back out into space. However, certain gases in our atmosphere, such as carbon dioxide, methane and water vapor, work like a blanket to retain much of that heat. This helps to warm our atmosphere. The gases do this by absorbing the heat and radiating it back to Earth’s surface. These gases are nicknamed “greenhouse gases” because of their heat-trapping effect. The increase in the levels of these greenhouse gases due to our contributions such as burning of fossil fuels and deforesting gives rise to its effect to global warming.

So, yes there is still Chemistry in it's process.

]]>https://forum.kiasuparents.com/post/1978992https://forum.kiasuparents.com/post/1978992Mon, 01 Jun 2020 12:00:14 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Mon, 01 Jun 2020 09:34:23 GMT]]>Hi,


Just a random question…how are these so-called greenhouse gases cause global warming? Is there a chemical reaction taking place?

]]>https://forum.kiasuparents.com/post/1978968https://forum.kiasuparents.com/post/1978968Mon, 01 Jun 2020 09:34:23 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Sun, 31 May 2020 10:30:19 GMT]]>Hey there parents!


Are your kids now revising? If they have landed on the topic of the periodic table, maybe this Q&A could help.

Which of the following statements is incorrect for an element with six valence electrons in its atoms?
A.\tThe element must be a gaseous non- metal.
B.\tThe element must be placed in Group VI of the Periodic Table.
C.\tIts atoms can gain two electrons during a chemical reaction.
D.\tIts atoms cannot form an ionic bond with atoms of another element in the same group. \t\t\t\t\t\t\t\t\t

Answer: A

Explanation: An element with six valence electrons need not be a gas. If the AT of the element is large, there will be significant intermolecular forces which hold the atoms together, requiring a large amount of energy to separate the atoms.

Jaiyous!

]]>https://forum.kiasuparents.com/post/1978802https://forum.kiasuparents.com/post/1978802Sun, 31 May 2020 10:30:19 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Sun, 31 May 2020 10:22:39 GMT]]>

chay58\" post_id=\"1978344\" time=\"1590722909\" user_id=\"185479:

Hi there!

I don't know if I landed the appropriate forum but may I ask if you have assessment books? or do you have an idea where I could find a most recent assessment books?

Thanks!
Hi chay58,

I'll be sending you PM for details on this.

Regards,
UPTAS

]]>https://forum.kiasuparents.com/post/1978800https://forum.kiasuparents.com/post/1978800Sun, 31 May 2020 10:22:39 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Fri, 29 May 2020 03:28:29 GMT]]>Hi there!


I don’t know if I landed the appropriate forum but may I ask if you have assessment books? or do you have an idea where I could find a most recent assessment books?

Thanks!

]]>https://forum.kiasuparents.com/post/1978344https://forum.kiasuparents.com/post/1978344Fri, 29 May 2020 03:28:29 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Thu, 28 May 2020 01:48:52 GMT]]>Here’s another periodic table interpretation trick in "guessing" the state of the element in the environment.


Which of the following would be a solid at room temperature?
A. Xenon\t\t\t\t\tB. Radon
C. Astatine\t\t\t\t\tD. Bromine \t \t\t

Answer: C

Explanation: Astatine is below iodine in the Group VII. Iodine is a solid and, by deduction, astatine would also be a solid. All the other options are elements in gaseous state.

]]>https://forum.kiasuparents.com/post/1978104https://forum.kiasuparents.com/post/1978104Thu, 28 May 2020 01:48:52 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Thu, 28 May 2020 01:46:43 GMT]]>hey there students and parents!



I know some of you have started revising. I hope this forum have helped you with it.
For today, let’s review some periodic table arrangement patterns.

Which of the following properties is used to arrange elements in the Periodic Table?
A. Reactivity\t\t\t \tB. Mass number
C. Atomic number\t\t\tD. Neutron number\t \t

Answer: C

Explanation: The elements are arranged according to the number of protons in the nucleus, i.e., the atomic number.

]]>https://forum.kiasuparents.com/post/1978103https://forum.kiasuparents.com/post/1978103Thu, 28 May 2020 01:46:43 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Mon, 25 May 2020 09:19:38 GMT]]>

wooyin08\" post_id=\"1977670\" time=\"1590384582\" user_id=\"185522:

Hello,

I'm new in Kiasu and I purposedly created my account hoping I can find a venue where I can ask help for my studies since my parents cannot afford to get a tuition for myself. Then came across with this thread so now I'd like to try if I can get help here..

I have this problem in my Chemistry and not so confident with my answer yet.

When potassium chlorate(V) KClO3, is heated at its melting point, it disproportionates to potassium chlorate(VII) KClO4 and potassium chloride.

What is the maximum number of moles of potassium chlorate(VII) which could
be produced from 0.1 mol of potassium chlorate(V)?

Thanks.
Hi wooyin,

Given your circumstance, may I know if you are in Sec or JC? So I'll know where you could get the best help.

Thanks for having great time scanning through this forum!

]]>https://forum.kiasuparents.com/post/1977725https://forum.kiasuparents.com/post/1977725Mon, 25 May 2020 09:19:38 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Mon, 25 May 2020 05:58:07 GMT]]>

uptas\" post_id=\"1977142\" time=\"1590062123\" user_id=\"184429:

Hi parents and students!

SHaring you some notes on REDOX.
Here's a list of the common oxidising agents

MnO4– is reduced to Mn2+ under acidic conditions.

Cr2O72– is reduced to Cr3+ under acidic conditions.

Halogens are reduced to halides.

Fe3+ is reduced to Fe2+.

H2O2 is reduced to H2O.

Hello,

Thanks for sharing these. But, can substances act as both oxidizing agents and reducing agents? If yes, can you show us an example. Thanks!

]]>https://forum.kiasuparents.com/post/1977681https://forum.kiasuparents.com/post/1977681Mon, 25 May 2020 05:58:07 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Mon, 25 May 2020 05:29:42 GMT]]>Hello,


I’m new in Kiasu and I purposedly created my account hoping I can find a venue where I can ask help for my studies since my parents cannot afford to get a tuition for myself. Then came across with this thread so now I’d like to try if I can get help here…

I have this problem in my Chemistry and not so confident with my answer yet.

When potassium chlorate(V) KClO3, is heated at its melting point, it disproportionates to potassium chlorate(VII) KClO4 and potassium chloride.

What is the maximum number of moles of potassium chlorate(VII) which could
be produced from 0.1 mol of potassium chlorate(V)?

Thanks.

]]>https://forum.kiasuparents.com/post/1977670https://forum.kiasuparents.com/post/1977670Mon, 25 May 2020 05:29:42 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Sun, 24 May 2020 00:28:03 GMT]]>Hey there parents/students,


TO compliment the previous post, here are the common redusing agents and how they become such in Redox reactions.

Fe2+ is oxidised to Fe3+.

H2O2 is oxidised to O2.

Halides are oxidised to halogens.

C2O42– is oxidised to CO2.

S2O32– is oxidised to S4O62– by I2 and to SO42– by other stronger oxidising agents like Cl2.

FeC2O4 is oxidised to CO2 and Fe3+.

Wishing you all the best in your reviews!

PM us if you wish to have a copy of these notes, compiled!

]]>https://forum.kiasuparents.com/post/1977412https://forum.kiasuparents.com/post/1977412Sun, 24 May 2020 00:28:03 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Thu, 21 May 2020 11:55:23 GMT]]>Hi parents and students!


SHaring you some notes on REDOX.
Here’s a list of the common oxidising agents

MnO4– is reduced to Mn2+ under acidic conditions.

Cr2O72– is reduced to Cr3+ under acidic conditions.

Halogens are reduced to halides.

Fe3+ is reduced to Fe2+.

H2O2 is reduced to H2O.

]]>https://forum.kiasuparents.com/post/1977142https://forum.kiasuparents.com/post/1977142Thu, 21 May 2020 11:55:23 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Tue, 19 May 2020 11:21:24 GMT]]>Hey there parents!


Are you helping your kids in their revisions review? just visit this forum to have something Q&A or tips and tricks to share with them.

For tonight, we are opening a new topic on electrolysis. Starting off with this question.

What are the products at the electrodes when an aqueous solution of copper(II) sulfate is electrolysed using carbon electrodes?
\t Anode\t Cathode
A\t Oxygen Copper
B\t Hydrogen\tOxygen
C\t Copper\t Hydrogen
D\t Oxygen\tHydrogen

Answer: A

Explanation: Water is preferentially discharged at the anode to form oxygen, while copper is deposited on the cathode.

]]>https://forum.kiasuparents.com/post/1976763https://forum.kiasuparents.com/post/1976763Tue, 19 May 2020 11:21:24 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Sun, 17 May 2020 12:47:32 GMT]]>You’re most welcome chay!


We’re really looking out to help kids in their Chemistry studies, especially this HBL.
We hope to share more Tips and tricks and Q&As to you in order to help you develop your passion for Chemistry.

Watch out for more of our posts!

Cheers!

]]>https://forum.kiasuparents.com/post/1976402https://forum.kiasuparents.com/post/1976402Sun, 17 May 2020 12:47:32 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Sat, 16 May 2020 05:48:05 GMT]]>Great Forum!


Been looking out for some Chemistry study sources for some time because of the upcoming exams. ughh…
having hard time studying though because of the HBL, I seem to lack motivation.
Can I ask for an advice on how and where to begin with my review?

Thanks!

]]>https://forum.kiasuparents.com/post/1976184https://forum.kiasuparents.com/post/1976184Sat, 16 May 2020 05:48:05 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Fri, 15 May 2020 01:47:19 GMT]]>Hey there Students and parents!


We hope you have started doing the review for the upcoming exams. 5 months preparation time is a great start as you can have a long time to decipher how your study habits look. You can have enough time to assess what kind of reviewing is effective for you or not.

anyways, for today, we are sharing with you a Q&A on ACIDS and BASES topic.

Which compound should not be used to prepare magnesium chloride by reaction with hydrochloric acid?

A. Magnesium\t\t\t\tB. Magnesium oxide
C. Magnesium nitrate\t\t\tD. Magnesium carbonate\t\t

Answer: C

Explanation: Magnesium chloride is a soluble salt and is prepared by reaction of acids with either a metal, base or carbonate. There is no visible reaction between magnesium nitrate and hydrochloric acid. There is also no undissolved solid left to indicate that all the acid has reacted.

]]>https://forum.kiasuparents.com/post/1975938https://forum.kiasuparents.com/post/1975938Fri, 15 May 2020 01:47:19 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Thu, 14 May 2020 10:19:42 GMT]]>Hi Parents!


If your son or daughter has some Chemistry A or O levels assignment, feel free to post it here so we can assist in answering them.

Cheers!
UPTAS

]]>https://forum.kiasuparents.com/post/1975850https://forum.kiasuparents.com/post/1975850Thu, 14 May 2020 10:19:42 GMT<![CDATA[Reply to Chemistry Trivia (Q&amp;A and some tips and tricks) on Tue, 12 May 2020 11:36:56 GMT]]>For tonight’s Q&A,


Which of the following explains why the speed of a chemical reaction is increased when a solid reactant is ground into a finer powder form?

A.\tThe density of the reactant is increased.
B.\tThe concentration of the reactant is increased.
C.\tThe activation energy of the reaction is decreased.
D.\tMore reactant particles are exposed to collisions with other particles.\t

Answer: D

Explanation: When the solid reactant is ground into powder form, its surface area is greatly increased, leading to a much larger exposed area for contact with other reacting particles.

]]>https://forum.kiasuparents.com/post/1975435https://forum.kiasuparents.com/post/1975435Tue, 12 May 2020 11:36:56 GMT