Chemistry Question.

[joonkimdds]

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Here are two unknown M questions.

"A sample of 0.600 mol of a metal M reacts completely with excess florine to form 46.8 g of MF2 . How many moles of F2 reacted? and how many grams of M are in the 0.600 mol of M?"

Here is the second question

"A sample of 0.800 mol of a metal reactes completely with excess florine to form 49.45g of MF2. Find the amount in grams of M in 0.800 mol of M."


Help me out plz 🙂

 

[tom3]

lol. honestly, are you posting just to raise your post count or something? don't tell me that you got A's in gen chem... and you can't even answer these? cmon..

 

[joonkimdds]

lol. honestly, are you posting just to raise your post count or something? don't tell me that you got A's in gen chem... and you can't even answer these? cmon..

so then, can u do it?

 

[Blackstars]

so then, can u do it?

If you cannot do this easy problem, you need to stop wasting time on SDN and study. Hmmm, 4.0 science gpa and you cant do this problem.

 

[joonkimdds]

"A sample of 0.800 mol of a metal reactes completely with excess florine to form 49.45g of MF2. Find the amount in grams of M in 0.800 mol of M."

I did both of these questions about 1 year ago and I forgot how to do it. Even at that time, it was one of those questions I missed on the test...

For the question above...what i did was.
M + 2F ->MF2
since M is limiting reactant and has 0.8 mol, MF2 also has 0.8 mol with 49.25g.

MF2 has 1.6 mol of F(since F also need to follow what limiting reactant has and there are 2 F so 0.8 times 2 = 1.6 mol of F)
1.6 mol of F has 30.4g of F(since F has 19g/mol).
And then Finally mass of M = 49.45g - 30.4 = 19.05g
but answer isn't 19.05 and so I got it wrong...and I don't know what the real answer is.

the other question....I also got it wrong due to same reason.
so now...could u help me ?

 

[shengx12]

"A sample of 0.600 mol of a metal M reacts completely with excess florine to form 46.8 g of MF2 . How many moles of F2 reacted? and how many grams of M are in the 0.600 mol of M?"
0.6 Mole
24 Gram

"A sample of 0.800 mol of a metal reactes completely with excess florine to form 49.45g of MF2. Find the amount in grams of M in 0.800 mol of M."
19.05 Gram

Help me out plz
"no problem"

 

[joonkimdds]

"A sample of 0.600 mol of a metal M reacts completely with excess florine to form 46.8 g of MF2 . How many moles of F2 reacted? and how many grams of M are in the 0.600 mol of M?"
0.6 Mole
24 Gram

"A sample of 0.800 mol of a metal reactes completely with excess florine to form 49.45g of MF2. Find the amount in grams of M in 0.800 mol of M."
19.05 Gram

Help me out plz
"no problem"

the second problem, as i wrote there, i had 19.05 and she took of points.
That's why I have this post. and could u also show ur work plz?

 

[joonkimdds]

If you cannot do this easy problem, you need to stop wasting time on SDN and study. Hmmm, 4.0 science gpa and you cant do this problem.

If u can't do it, just don't say anything, cuz that doesn't help at all and u makes it waste of time being here.

 

[GCT]

the value of 19.05 is the right answer, although it may not be precise. Be practical about this.......you know that the metal will have an formal charge of 2+, group two elements that is. Go to http://www.webelements.com and click on some of the first group II metals, Be, Mg, Ca, find the flourides for each cation.

This is a realistic problem, it's based on real world examples. We know that .8 moles of a certain metal flouride will give us 49.45grams, try magnesium. What's .8 moles of 62.3 grams/mole...it's 49.45 right? You can verify that .8 moles of magnesium will give you approximately 19.04 grams. There's nothing wrong with your answer.

 

[joonkimdds]

the value of 19.05 is the right answer, although it may not be precise. Be practical about this.......you know that the metal will have an formal charge of 2+, group two elements that is. Go to http://www.webelements.com and click on some of the first group II metals, Be, Mg, Ca, find the flourides for each cation.

This is a realistic problem, it's based on real world examples. We know that .8 moles of a certain metal flouride will give us 49.45grams, try magnesium. What's .8 moles of 62.3 grams/mole...it's 49.45 right? You can verify that .8 moles of magnesium will give you approximately 19.04 grams. There's nothing wrong with your answer.

Can I sue my professor ...-_-;

 

[GCT]

tsk, tsk now...it happens😉