havent studied a word from 2 days gonna start in the morning IA (XPC addictionYeah, start studying. The main problem.
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Biology; Chemistry; Physics: Post your doubts here!
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The first three, if you simplify them and divide, have the empirical formula:
A. C2H4 - CH2
B. C3H6 - CH2
C. C4H8 - CH2
D. C8H8 - CH.
So, D is the answer.
can u please tell the year from which this question is from, i can explain after reading the er
Saad Mughal maybe u can explain it
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Same here. Haven't done anything except papers (which I've also been asked to do by people here).havent studied a word from 2 days gonna start in the morning IA (XPC addiction
We're dead.
and people still think we know everythingSame here. Haven't done anything except papers (which I've also been asked to do by people here).
We're dead.
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Easy. The alloys are harder because the layers of atoms of the metal can no longer slide over one another.can u please tell the year from which this question is from, i can explain after reading the er
saad maybe u can explain it
Now, for this to be true, option B and C are rejected because density and conductivity have nothing to do with this.
For A, it is true since when a metal with a larger atom (by size) is mixed with a metal of smaller atom (size), the layers can no longer slide over each other because of the irregularities.
Option D is rejected for 2 reasons, an atom can have a greater mass with the same atomic radius (elements in the same period) AND mass is directly related to density, so it does not have an effect on the sliding properties of metals.
Hope that seems logical enough!
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People ask easy questions, we answer them, people think we're geniuses. However, when we do papers, we come across questions that make us feel like retards.
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that is so simple ....it looks complicated thanks once again....
thanks i knew how it was but did not how to explain itEasy. The alloys are harder because the layers of atoms of the metal can no longer slide over one another.
Now, for this to be true, option B and C are rejected because density and conductivity have nothing to do with this.
For A, it is true since when a metal with a larger atom (by size) is mixed with a metal of smaller atom (size), the layers can no longer slide over each other because of the irregularities.
Option D is rejected for 2 reasons, an atom can have a greater mass with the same atomic radius (elements in the same period) AND mass is directly related to density, so it does not have an effect on the sliding properties of metals.
Hope that seems logical enough!
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22 Sulfur dioxide reacts with aqueous bromine according to the following equation.
SO2(g) + Br2(aq) + 2H2O(l) → H2SO4(aq) + 2HBr(aq)
Which element has been oxidised?
A bromine
B hydrogen
C oxygen
D sulfur
answer is d can u tell me oxidation state of every option....
SO2(g) + Br2(aq) + 2H2O(l) → H2SO4(aq) + 2HBr(aq)
Which element has been oxidised?
A bromine
B hydrogen
C oxygen
D sulfur
answer is d can u tell me oxidation state of every option....
A 0 to -1
B +1 to +1
C -2 to -2
D +4 to +6
remember hydrogen has always +1 and oxygen always -2
they can never be oxidised or reduced
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but hydrogen is also present in sulphuric acid....
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hahahaha i am prayng for u ....I'm not going to post another answer till u tell me that u have started praying for me
both hydrogen are +1, sulfur is +6 and 4 oxygen are -2 each so
+1+1+6-2-2-2-2=0
Anyways I'm going, have 2 sleep now.hahahaha i am prayng for u ....
oh and remember hydrogen is -1 in hydrides (some metal compunds of hydrogen e.g. sodium hydride) although you will rarely face it in O-Levels
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Bara acha tariqa hai dua'en maangny ka.I'm not going to post another answer till u tell me that u have started praying for me
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hahahaahahhaahBara acha tariqa hai dua'en maangny ka.
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aaaa dis myt be a bit TOO dumb. but aniways.....2 questions that i couldnt understand;
1) 4 Grams of carbon reacts with 6 grams of oxygen. Calculate the moles of carbondioxide formed.
2)10 grams of carbon reacts with 10dm^3 of oxygen at RTP. Calculate the moles of carbondioxide formed.
1) 4 Grams of carbon reacts with 6 grams of oxygen. Calculate the moles of carbondioxide formed.
2)10 grams of carbon reacts with 10dm^3 of oxygen at RTP. Calculate the moles of carbondioxide formed.
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1. C + O2 ---> CO2aaaa dis myt be a bit TOO dumb. but aniways.....2 questions that i couldnt understand;
1) 4 Grams of carbon reacts with 6 grams of oxygen. Calculate the moles of carbondioxide formed.
2)10 grams of carbon reacts with 10dm^3 of oxygen at RTP. Calculate the moles of carbondioxide formed.
1 mole of carbon reacts with 1 mole of oxygen to form 1 mole of carbon dioxide.
If you calculate the moles using the given masses,
4/12 mole : 6/32 mole
0.33 mole : 0.1875 mole
So, carbon is in excess.
The ratio is 1:1 = 1 so,
Moles of CO2 = 0.1875 moles.
2. At RTP is mentioned,
Convert both quantities to moles,
10/12 moles : 10/24 moles
0.833 moles : 0.4166 moles.
So, again, carbon is in excess.
The ratio is 1:1 = 1 so,
Moles of CO2 = 0.4166 moles.