Hey Andriy. I hope that you are having a great day/night. i think you made a mistake when you were calculating the number of atoms in a H3PO4 compound and you didn't multiply the answer by 8. the reason that I'm telling this is that we have 8 atoms in one compound of H3PO4, which are 3 Hydrogen atoms, 1 Phosphorus atom and 4 oxygen atoms and they make up 8 atoms. the answer that you got which is 1.2 * 10^20 is the answer for the number of H3PO4 molecules and in order to obtain the number of atoms, we should multiply this number by 8 which means the answer should be 9.6 * 10^20. I'm looking forward for your response. Best regards.
You are absolutely correct! Great work, making the distinction between atoms and molecules. I will pin this message for everyone to see the mistake, and I will fix the video in the near future! 11:20
Man I sure do hope you finish this series before the 13th, that's the day for the IMAT exam in my country. Would be really appreciated if you did, i'm almost done with all revision and i'll spend the last days doing past papers. You've been a lifesaver with this series : )
Ion with positive charge means it lost electrons, it’s a cation. Ion with negative charge means it won electrons, it’s an anion. The number of ions gained or lost is indicated by the *small* number at the end of the molecule for example CO3 ²- . That means the molecule gained two electrons. In cases like NH4+ where there’s no number to indicate the amount of electrons gained or lost then it means NH4+ just lost 1 electron. In conclusion the sign tells wether it gained or lost electrons and the small number tell you how many.
Hey Andriy. I hope that you are having a great day/night. i think you made a mistake when you were calculating the number of atoms in a H3PO4 compound and you didn't multiply the answer by 8. the reason that I'm telling this is that we have 8 atoms in one compound of H3PO4, which are 3 Hydrogen atoms, 1 Phosphorus atom and 4 oxygen atoms and they make up 8 atoms. the answer that you got which is 1.2 * 10^20 is the answer for the number of H3PO4 molecules and in order to obtain the number of atoms, we should multiply this number by 8 which means the answer should be 9.6 * 10^20. I'm looking forward for your response. Best regards.
You are absolutely correct! Great work, making the distinction between atoms and molecules. I will pin this message for everyone to see the mistake, and I will fix the video in the near future! 11:20
Man I sure do hope you finish this series before the 13th, that's the day for the IMAT exam in my country. Would be really appreciated if you did, i'm almost done with all revision and i'll spend the last days doing past papers. You've been a lifesaver with this series : )
+100000000000000000000000000
Thanks a bunch 🙏👍
thanks!
Hi thank you so much for your hard work! Would you please please download the last video of chemistry before the test?
There will be a new video up this Friday
Make a video on organic chemistry asap please!
Is the mass number/atomic number going to be given in the exam or do we have to memorize the entire periodic table?
Thanks for the video please can I get email to ask questions?
You know you are a lifesaver,Right?
❤️
how can i calculate the number of moles without a calculator
Facts
B. Indicate the number of electrons lost or gained in forming these ions:
1. NH4
+
2. CO3
-2
3. Au+3
4. OH-
5. SO4
-2
How can i do this? Help me
Ion with positive charge means it lost electrons, it’s a cation. Ion with negative charge means it won electrons, it’s an anion. The number of ions gained or lost is indicated by the *small* number at the end of the molecule for example CO3 ²- . That means the molecule gained two electrons.
In cases like NH4+ where there’s no number to indicate the amount of electrons gained or lost then it means NH4+ just lost 1 electron.
In conclusion the sign tells wether it gained or lost electrons and the small number tell you how many.
but calculators are not allowed
You will be given numbers that are easier to calculate. However, the same principles will apply.