A weak acid HA has a Ka of 3.8×10-9. where A- is the conjugate base. The salt NaA has a fw=197.2 g/mol. A buffer is made by dissolving 18.22 g of solid NaA in 400.0 mL of 0.350 M HA solution. Assume the volume stays constant when the solid is dissolved. A. What is the pH of this buffer?  B. The pH is changed to 7.50 by adding a certain amount of . (type in the blank one of these choices: strong acid, strong base, water) C. What is the ratio of conjugate base to acid at this new pH?   Give a decimal answer with correct sig figs. Show work on your upload that supports your answers. Partial credit is possible!  

Adding which of the following will cause the solubility of the slightly soluble salt silver carbonate Ag2CO3 to increase? Select ALL that are true.  

Which one of the following is likely to be a tridentate chelate?

An indicator H2In is diprotic with pKInd1=5.2 and pKInd2 = 10.4. The colors of the related species are: H2In is red, HIn- is blue and In2- is yellow. What color would you expect to see if this indicator is added to a solution with a concentration of of 4.0×10-11 M?

Based on what we learned in lecture, Type the expected complete ground state configuration for the transition metal 44Ru . Type your answers in the provided space.  To make it easy to type, simply leave one space between each sublevel as shown, do not bother with superscripts, no need for commas or parentheses. This should not be an image or be typed using the equation editor. Complete means start with 1s2 2s2 etc…

Consider the made-up transition metal Rikerium, symbol Rk. Write the formula for each of the following compounds (which do not exist!): Type your answers in the provided space, using the sub T2 and superscript T2 buttons in the question menu. A.  ammonium diaquatetracyanorikerate(II)  B.  pentaamminehydroxorikerium(III) phosphate

The sea slug is a(n) _____.

A 5.00 mL sample of an unknown concentration triprotic acid solution is pipetted into a beaker, then titrated with 0.3 M NaOH using an appropriate indicator. This indicator changes color at the 2nd equivalence point which occurs at 2.4 mL of titrant. The concentration of the triprotic acid solution is ______M ?  Show your work in the file you upload. Enter your answer in decimal form, with correct sig figs, no units.

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A characteristic that is shared by snakes and birds is _______