lulu78

brass is a subtitutional alloy consisting of a solution of copper and zinc. a particulae sample of red brass consisting of 80% copper and 20% zinc by mass has a density of 8750kg/m^3. a. what is the molality of zinc in the solid solution and B. what is th...

Dr BOB can you explain this to me. I am so struggling with this subject. during a typical breathing cycle the CO2 concentration in the expired air rises to a peak of 4.6% by volume. Calculate the partial pressure of the CO2 at this point, assuming 1 bar o...

At 63.5 degreesC, the vapour pressure of H2O is 23.3kPa and that of ethanol is 53.3kPa. A solution is made by mixing egual masses of H2O and C2H5OH. a. what is the mole fraction of ethanol in the solution? b. assuming ideal-solution behaviour, what is the...

0.1m aqueous solution of HCl and 0.1m aqueous solution of C6H12O6. calculate the boiling point of each i know the eq. dTb=Kbm but i have no temperatures. this is the question

Lysozmyne is an enzyme that breks bacterial cell walls. A solution containing 0.150g of this enzyme in 210ml of solution has an osmotic pressure of 0.217kPa at 25*C. What is the molar mass of Lysozmyne? I cant find the chemical formula anywhere. I have us...

how many mls of glycerol (FW= 92.1; density=1.26g/ml) must be used to make 250ml of a 0.15 M solution

what are the parts of the cerebrum the receive and interpret somatic senory signals? I have searched my ext just cant find the answer.

blood helps maintain homeostasis by all of these mechanisms EXCEPT: a. eliminates waste products b. protects about foreign substances c. transports nutrients and gases d. regulates pH e. clot formation I don't totally understand this question. I know that...

i don't understand why i cant get this. I have the answers but i don't get them. i did 20g/65.4g/mol= 0.306mol, then 0.306mol/0.1kg= 3.058m, but the answer they have is 3.82m. then the next step still confuses me.

dumb question? why is it 100g not 0.1kg? the rest i get/got.

so the rest is good then?

i have another question on this silly topic further up if your fresh and ready again.

any help will do?

can you show me. i'm confused.

thenkyou. i missed reading that pert on that page before. i knew it was something simple. i now have parts A and B but how do you work out C? i have the mole fraction of ethanol from part A. why is it not the same?

i thought pi was 0.217? the answer in the text is 1.39*10^4g

is the Kb 0.51 just standard BP of water? i think that's where i'm getting lost.

so do i use the moles i would have from part A? surely not, becayse they just give me the mole fraction of the solution. what do i use? i have the answer of 0.472- don't know how to get it. i feel so dumb and have my exam on 23rd.

The question is basically asking which one of the 5 are not involved with the blood homeostasis properties. I have since figured it out. the answer is A as it is not homeostasis/negative feedback. all the others can be reverse/taken to completion.