Infinity

Hi, but how do you make an quantitative experiment to test that? Also, how about the polar and non-polar stuff? it seems harder to test whether a covalent compound is polar or not.

So...how do you carry out an experiment to test if these unknowns are covalent (polar or non-polar) or ionic?

Unknowns:

C6H12O6 --NaCl --CH4N20 --C6H8O7

Is it calculus-based? Do you apply Calculus in IB Physics?

What are the textbooks that you use for IB Physics? IBH Physics? Or if you're not doing IB/H Physics you can still recommend textbooks for AP Physics B or AP Physics C. Or even better, you can recommend general introductory physics textbooks (but I'd prefer first and second year university physics textbooks).

The purpose is that I'm doing extensive research on general physics in preparation for the IB Physics.

Thanks for any recommendation.

Energy itself is a state function if it the situation is conservative, such as with gravity and electric fields. Enthalpy itself relates to the chemical energy released/absorbed in an open system. The q relates to the temperature change (internal energy) while w relates to the work in expanding against the surroundings. It is simply a statement relating to the conservation of energy. I don't know why you're so confused with this. By the way q is a state function, it relates to the initial and final temperature, the w is a general expression for the energy lost in expansion.

Thanks a lot. This is the kind of answer I've been expecting to see.

So why is heat a path function ? Is it because when you use different method of changing temperature, the heat will be different? The same concept applies for work?

Now comes the ultimate question again: How is it possible that two path functions (heat and work, for example) add up to a state function (change in internal energy)? The formula is: (delta)E = q + w.

I've looked at it for several times but couldn't understand how it is possible for two path functions to become one state function.

well i went through this stuff in physics

I'm going through this stuff in Thermochemistry.

thats more of a physics question

No, it's not. It's more of a thermochemistry question.

How is it possible that two path functions (heat and work, for example) add up to a state function (change in internal energy)? Why is energy a state function? Why is heat a path function? Why is work a path function?

Many thanks.

is it because it has something to do with the nervous system? like it will deplete all the cellular K in heart preventing it from contracting?

Good question. Maybe it just compresses your heart and prevents it from beating normally and slows down the pace of beating and then the heart gets weaker and weaker and then it dies out?

KCl is also used in lethal injections to stop the heart of the condemned.

So it is used for punishment--and perhaps also for suicide.

What is the minimum lethal dose usage for it?

it's KCl. i has no explosive properties

I knew that! I was quite surprised that urza said that it's used as bombs...I was like this

its used in bombs... many nations used it to devolp mines and other explosives during WWII

How can it be used to make bombs? What is the formula for creating explosives with KCl?

How many uses does the ionic compound Potassium Chloride (KCl) have?

The sigma bonds C2H6 (Ethane) is an example of Covalent Bonding.

In atomic level there is sharing of electrons

For example in C2H6 the sigma bonds overlap each other causing

electrons to be shared.

 

 

I should also say that this is a very basic question. I would be very concerned if you are lacking the basic knowledge of Covalent bonding' date=' Ionic bonding, and Metallic Bonding.[/quote']

 

xroxybabix, don't forget that there are two types of bonding in covalent bond: pi bond and sigma bond.

 

Like FVT, I would be concerned if you don't know this knowledge which should be taught in your Basic Chemistry class.

Please help me. I really need help for this lab.

Please help me on this lab.

Alka-Seltzer Lab

Purpose:

You work for Safeway Inc. and are testing the quality of the effervescent tablet that is sold as an alternative to Alka-seltzer. You want to make sure that the tablet delivers as much relief as possible and you can measure this by measuring the amount of bubbling. You will predict the amount of bubbling theoretically possible and compare it to the actual amount of bubbling.

The reaction that occurs is: NaHCO3 + HC6H7O7 --> NaC6H7O7 + CO2 + H2O

HC6H7O7 = Citric Acid

Hypothesis:

* Predict the amount of CO2

* Don't forget to consider which reactant is limiting…show all your calculations to justify your prediction

* Hypothesis should use the words theoretical yield and limiting reactant

Materials:

* Safeway brand Effervescent Tablets

* You need to determine the rest...

Procedures:

* One detail that I'm giving you… You will be dissolving the tablet in 100 mL of water in a 150 mL beaker

* You work out the details...

Data:

* Don't forget to include data from the package…

* Theoretical yield, actual yield and percent yield

Analysis:

* Calculate the amount of CO2 given off (actual yield) and percent yield.

* Calculate volume at STP

* Show all calculations and units

Error Analysis:

* Did you get alot more CO2 than you thought? Here is one possible error you need to discuss:

o Citric Acid was not a reactant and therefore did not directly control the amount CO2 made

o The reaction occurring could be: NaHCO3 --> CO2 + NaOH

o The citric acid is used to neutralize the base (NaOH) formed so that it doesn't upset your stomach

* You should calculate a new theoretical yield based on the amount of NaHCO3

* Then calculate a new percent yield (hopefully it will be less than 100%...)

* Describe other sources of error that could be factors

Conclusion:

* Standard conclusion - use template if necessary

How do you do the calculation in bold? Please help! Thanks a lot.