All Chemistry Questions & Answers
|Calculating molarity and molality.||
A sample of potassium aluminum sulfate 12-hydrate, KAl(SO4)2.12H2O, containing 118.6 mg is dissolved in 1.000 L of solution. Calculate the following for the solution:
a. The molarity of KAl(SO4)2.
b. The molarity of (SO4)2
|What does periodicity mean in chemistry?||
What does it mean? how do i know waht it is? how do i find it? And can you please give a number of examples? thanx in advance!
|Palladium crystal has 2 bond lengths, Alpha and Beta. How much energy does it take to go from alpha to beta?||
A bond between two palladium can either be in the lowest engery state called alpha and a more excited state, called beta. How much energy does it take to go from alpha to beta? Or whats the difference in the bonds engery?
2O3->3O2 deltaH=-285 kJ/molrxn
|Which reference electrode to select for electrochemical measurements? The one with Vycor or ceramic frit?||
Is there any significant difference in quality and accuracy between reference electrode with Vycor frit (porous glass attached with heat-shrink tube) and the one
equipped with ceramic frit (molten in the glass tube) like in this example https://redox.me/coll
|Percentage By Mass Calculation||
A 4.675g sample of limestone (impure CaCO3) was treated with 375ml of 0.261 molL^-1 hydrochloric acid. After the reaction was over, the mixture was filtered and a 25 ml sample of the filtrate required 17.62ml of 0.0517 molL^-1 barium hydroxide solution for complete neutralisation.
|How do I find the initial energy of an electron given the wavelength and the final energy||An electron jumps to the n = 4 level of a hydrogen atom after absorbing a photon of wavelength 1875 nm. What energy level did the electron move from? I haven't found equations for how to to find the energy absourbtion, just emission.|
|What is the percentage of cocaine in the mixture?||
A sample of cocaine, C17H21O4N, is diluted with sugar, C12H22O11. When a 1.00 mg sample of this mixture is burned, 2.00 mg CO2 is formed. What is the percentage in this mixture?
|Why are they dividing by 2 to find average?||
Why are the dividing by 2 for the average rate? They should divide only when comparing, right? Where am I going wrong?
|Can someone please explain and show me how to di this question please....||
Jacy bought a gold necklace weighing 21.3 grams from the flea market. She filled a graduated cylinder with water to the 5.0mL mark and dropped her necklace in. The level in the graduated cylinder rose to 704mL. is her necklace real or fake?