MrsHeidi (Chemistry Question Help- Please Ma'am)
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MrsHeidi (Chemistry Question Help- Please Ma'am)
The number of moles of ions produced by the dissociation of 1 mol of MgCl2 is________.
What? Is it 2? My Leanna is taking this this year. Huge mistake I think.
I would appreciate any help. So much. Thanks. Thanks!!
MgCl2--->Mg(2+) + 2Cl (-)
1 mol of magnesium chloride dissociates into 1 mol of magnesium and 2 mol of chloride ions.
You basically look at how many molecules you have. You started off with one molecule, so you start off with 1 mole. Then, when you separated them, you have 1 mg ion and 2 cl ions. (The coefficients, which are the numbers in FRONT of the letters, reveal the # of moles.)
PS- I would get a local chemistry tutor *now*. Or, ask the teacher when his/her tutoring hours are. Has she already started school? EVERYONE needs a chemistry tutor...if not, they're lying...FYI. Everyone gets help, somehow, some way, somewhere... 
I never had a tutor and neither did Sarah! Sarah said she asked the teacher, or other kids in her class, when she had questions. I must have done the same. I had to take it in college, too.
I have to admit, I would love to take a class, just to be able to the experiments. That was fun! My favorite one was super-saturating a solution, then adding one more crystal and having it all turn into a crystal again!
The other one I liked was mixing hydrochloric acid and sodium hyroxide together, then boiling off the water and getting sodium chloride.
Doing things with Benedict's solution was also kind of fun! Figuring out an unknown chemical in chem class and figuring out an unknown bacteria in microbiology, was loads of fun!
I HATED chemistry in high school because I always found it so hard at age 17. I wasn't gifted in algebra either, so that is what made chemistry tough for me. I was a "humanities" student. I have always LOVED English; i.e. literature, creative writing. I have also always loved history.
I pleasantly surprised myself when I began working in pharmacy, and chemistry came to me like water off a duck. Also, in hairdresssing school, we had a fair amount of chemistry, and I aced it.
Maybe my brain hadn't matured yet in high school.
Thank you so much Heidi! That certainly helps.
I am looking for a tutor right now. Hopefully God will produce one.
Dawn777- that's great that you and Sarah are so blessed with chemistry knowledge and a good teacher. Unfortunately we are not lucky.
Thanks again Heidi.
If Sarah would have needed help, though, my best friend and her DH are quite versed in math and science, and I think they would have been able to help us. Once in a great while, I did call up Edie and ask her a math question. Sarah is a brainiac. Since she has been in high school, she hasn't needed any help from me, and has gotten A's. It's a good thing, because I really don't remember that stuff!
That is great! Unfortunately, we need help with these things. Me and my regular children.
Don't feel bad about that, IloveTom. I think it is great that she has the interest to take Chemistry in highschool. Most people do need help. I am struggling right now in my classes at college because I need to take Chem and Calculus and I'm scared to death!
I'm going to school to become a teacher, but I hate math! I only want to teach up to 4th grade, though, so I should do okay! LOL!
Algebra and I are not friends! I just received a book called "Forgotten Algebra" to brush up on it before I take Calculus and Chem. I'm doing much better than I did in HS, and am surprising myself at how much I have retained!
Good luck on finding a great tutor for her. And Kudos for recognizing early on that she will do better with one. A lot of parents wait so long because they feel having a tutor means something it doesn't. I'm glad you aren't like that.
My oldest is a chemistry "genius", and here is what he says. His answer agrees with Heidi's.
"The answer is 3.
When MgCl2 dissolves (presumably in water), it dissociates into magnesium ions and chloride ions. Each MgCl2 forms one Mg (+) ion and two CL (-) ions.
One will have to memorize the common ions that have more than one atom - for example nitrate, sulfate, ammonium. Otherwise a salt or acid has
every atom becoming a separate ion.
Soluble metal hydroxides (alkaline) generally dissociate into metal ions and OH (-) ions."
Basically, when you mix an acid and a base, you get water and a salt. It's like having dancing partners and you just switch partners.
Example:
NaOH + HCl --> NaCl + OHH (or, H2O) You see how they "switched partners?" Na is now with Cl and the OH (hydroxide) is now with the other H.
That's what Ginny's son means.
And, the ions are like Sulfate (SO4) where the sulphur and oxygen just stay "stuck" to each other. I tell the kids that those partners are MARRIED!! LOL! (NH4 is ammonium and NO3 and NO4, are nitrite and nitrate.) So, sometimes you'll end up with a compound called "Sodium Sulfate" where the sodium stuck to the married couple like this NaSO4. Where sodium is lonely friend going on a date with the SO4 married couple. (Sulphur is married to the oxygen.)
Have you found a tutor yet? Like I said, everyone gets help...from a teacher, a friend, a tutor. It's WELL worth the money. I charged $35 an hour for high school kids. Commercial places often charge $50+ so it's best to go with a college student who needs the money or a local person who works out of their home. Ask around for recommendations from past students and their parents.
Where in AL are you? I lived in Huntsville and could refer you to someone who can help.
LOL, I could have REALLY used a chemistry tutor back in high school. I still think that I only passed the class because the teacher liked me. My whole group was dubbed "The Pyromaniacs". Wanna guess why?
CORRECTION from my son
I did do a little oops in that reply:
A Mg ion has two + charges, not one.
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