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secondary 3 | A Maths
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this is sec 3 chemistry , please help me
Date Posted: 4 years ago
Views: 489
ik this isnt amath but idh any money to purchase the premium so i rly hope people here can help me bcus i'm struggling :-(
Hang on
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First five.
Let me know if you need help in these.
1. Identifying ion charges
2. Naming of ion
3. Forming the chemical formula of the compound
Let me know if you need help in these.
1. Identifying ion charges
2. Naming of ion
3. Forming the chemical formula of the compound
Date Posted:
4 years ago
is it possible for u to explain to me how to get the ans & provide me w ans for the rest of the questions too ? i'm weaker in chemistry so :/
Ok, I will demonstrate the first few for your understanding, give me a few moments
thank you so much for helping me !
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The remaining
Date Posted:
4 years ago
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Some of the ion charges must be memorised, especially for more complex ones like nitrate, sulfate and carbonate. The forming of the formula is based on the attempt to balance out the charges.
Here is the first one for your reference.
Here is the first one for your reference.
Date Posted:
4 years ago
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Three more examples
Date Posted:
4 years ago
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Here are a few more; I have not completed the last three, you can try the last three on your own using the guidelines which I have provided in my demonstration.
Note the following.
1. You also need to know how to name a compound given its chemical formula. Numbers are not required except for rare cases (eg, MgCl2 is called magnesium chloride, we do not list out the 2, but FeCl3 is called iron (III) chloride; you will eventually find out some actions which require the writing of the Roman numerals.
2. For writing the formula, we write the cation (positive ion) first before the anion (negative ion). Do not write the charges once we have formed the compound (for example, magnesium chloride is MgCl2, not Mg2+Cl-2). Similarly, in the naming, the cation name comes before the anion name.
3. Blocks must always be followed. For example, if we want two nitrate ions to balance a calcium ion, we put (NO3)2 and not N2O6.
4. The list of such special blocks (containing more than one element) are as follows.
Ammonium, NH4 +
Hydroxide, OH -
Nitrate, NO3 -
Sulfate, SO4 2-
Carbonate, CO3 2-
There are more than this, but these are the basic five which you must memorise.
Note the following.
1. You also need to know how to name a compound given its chemical formula. Numbers are not required except for rare cases (eg, MgCl2 is called magnesium chloride, we do not list out the 2, but FeCl3 is called iron (III) chloride; you will eventually find out some actions which require the writing of the Roman numerals.
2. For writing the formula, we write the cation (positive ion) first before the anion (negative ion). Do not write the charges once we have formed the compound (for example, magnesium chloride is MgCl2, not Mg2+Cl-2). Similarly, in the naming, the cation name comes before the anion name.
3. Blocks must always be followed. For example, if we want two nitrate ions to balance a calcium ion, we put (NO3)2 and not N2O6.
4. The list of such special blocks (containing more than one element) are as follows.
Ammonium, NH4 +
Hydroxide, OH -
Nitrate, NO3 -
Sulfate, SO4 2-
Carbonate, CO3 2-
There are more than this, but these are the basic five which you must memorise.
Date Posted:
4 years ago
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The last three
Date Posted:
4 years ago
thank you for explaining it to me ! i've a btr understanding of it now :-)
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The bracket Roman numerals apply to the positive ion only!
Date Posted:
4 years ago
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