IGCSE CHEMISTRY SOLVED past paper 0620/23/O/N/23 - October / November 2023 Paper 23

[@fearnone0.o]

6:11 in q10, the multiplication that u told doesn’t work with the ions in silver nitrate as it’s a different number (3.01 x 10^24), so what the purpose of the ions in silver nitrate and how did they calculate that?

[@raidm1838]

cuh u just have to multiply the Avogrodas number with the numbers of ions in 1 mole so Avogrodas number * ion in silver nitrate(which are 2 ions) = 1.2 * 10^24 - for 1 mole and for iron oxide avagrodas number * ions in iron oxide (which are 5 ions) = 3.01 * 10^24 this answer is for 1 mole but were looking for 0.25 moles so: 3.01 * 10^24 x 0.25 moles = 7.5 * 10 ^ 23 ez shi

[@joy9648]

@fearnone0.o Ag is one ion, NO3 is another ion (so just multiply Avogadro constant by 2; not 5 like you did)

[@fearnone0.o]

@@raidm1838 how does silver nitrate has 2 ions and iron oxide has 5?? how in the world is this possible?? see, it’s AgNO3, so first Ag, second N, third O times 3 as its three times, and in iron oxide, 2 times Fe, and 3 times O, so both have 5 ions… correct me if i’m wrong

[@fearnone0.o]

@@joy9648 i see, but why aren’t N and O ions themselves, in NO3??

[@joy9648]

@@fearnone0.o N and O have intramolecular covalent bonds, while NO3 has intermolecular ionic bonds

[@annamontana2891]

TYSMMM

[@RitajAbdo-ju6jb]

Thank u🤍

[@funandgaming1551]

Will we be provided with the qualitative analysis in the exam?

[@funandgaming1551]

I gave the exam and we were provided with it in the atp

[@funandgaming1551]

From which KZbin account did you watch the experiment videos?

[@fearnone0.o]

no we won’t be provided, it’s only provided in atp

[@damiaamalin7364]

dr.mona, why is it c=c and not c-c like the formed bond ? whats the difference? 10:18

[@DrMonaSeif]

ethene ( alkene) is the reactant . Which has c=c. And ethane (alkane ) is the product. Alkane has only single bond between carbon atoms

[@aaaa-ri8is]

q10, you said Fe2O3 has 5 ions in one mol of Fe2O3. then wouldnt it be just 5×0.25?Sorry im confused ive never calculated number of ions before

[@aaaa-ri8is]

so 1mol has 6.02×10^23 ions or 5 ions??

[@DrMonaSeif]

1mole has 6.02×10*23 formulas and each formula contain 5 ions

[@fearnone0.o]

dr mona, can u pls tell me which metals react with cold water and which metals react with steam, because this reactivity question really confused me 19:49

[@DrMonaSeif]

Group one metals react with water to form metal hydroxide and hydrogen gas magnesium reacts with warm water or steam .

[@fearnone0.o]

@@DrMonaSeif just magnesium from Group II ??

[@Channels208]

why cant question 35 be B?

[@DrMonaSeif]

Because bromine has to be added in 2 adjacent carbons (two carbons that are next to each other ) and that is not happening in ( B)

[@Channels208]

@@DrMonaSeif thanks, is that the rule for most addition reactions?

[@xdSloshy]

@@Channels208bromine is added where the double bond breaks so it means it must add across two carbons next to each other . Apply this logic wherever needed.

[@Channels208]

@@xdSloshy thx

[@Cypacic]

Are yall having multiple choice in 1.5 hour like i am, if so, good luck yall