### Answer

There is a buffer system \$left(mathrmH_2 mathrmPO_4^--mathrmHPO_4 ^2- ight)\$ in blood the helps keep the blood \$mathrmpH\$ at around \$7.40 .left(mathrmK_mathrma mathrmH_2 mathrmPO_4^-=6.2 imes 10^-8 ight)\$(a) calculation the \$left /left\$ ratio at the normal \$mathrmpH\$ the blood.(b) What percentage of the \$mathrmHPO_4 ^2-\$ ions space converted to \$mathrmH_2 mathrmPO_4^-\$ as soon as the \$mathrmpH\$ goes under to \$6.80 ?\$(c) What percent of \$mathrmH_2 mathrmPO_4^-\$ ions room converted to \$mathrmHPO_4 ^2-\$ when the \$mathrmpH\$ goes as much as \$7.80 ?\$

You are watching: Which solution showed the greatest change in ph why

### Video Transcript

so we have a buffet i beg your pardon is H. Two P. 04 minus together the weak acid and also its conjugate bases HBO because that 2-. I'm certain the K. A. Where space weak acid is 62. I'm sounding an adverse eight and also we understand the ph Is walk to be 74. So that way Rh to add concentration 10 come the negative +74 Or 3.98. I'm sounding -8 Moller. So very first thing we're gonna execute is find the proportion of asset to base. So because that a buffer H plus concentration amounts to K. Times a concentration of your mountain over the concentration of your base. So our h to add we claimed was 398 time 10 come the -8. And also we'll plugin cahir that'll offer us a ratio of our acid base. So I'll give us a proportion of .64. Okay and then what we're gonna perform is we're walking to reduced the Ph 267 by converting few of the basic to acid. It s okay so ph is now 6.80. That means our brand-new H add to concentration Is 1.6. I'm sounding negative. 7 more. Therefore 1.6 I'm speak the -7 equals ca i beg your pardon is not going to change. Mhm. No. We're starting with 0.64 moles of mountain for every one mole that base. And also we're said we're walking to transform some that this base so minus X and also plus X. Because all of the once the base is converted, it's convert to weak acid. So but much weak base we shed we obtain that much weak acid. Therefore we'll simply go ahead and figure out the math here. The 2.58 is 64 to add X end one -X. And also then red overcome multiply. So 1.94 Is 358 X. So x comes out to be .54 animals. And we've asked what percentage. Okay, for this reason the percent Is walk to be our 54 moles over the original, which to be one time 100. So we're going to get 54 of our yeah. H p. 04 to minus to be converted come H two P. 04 minus. Okay, in this example we're just going to carry out the opposite. We're gonna convert some mountain to base. Okay, Our new ph A small bit higher. It's gonna be 780. So our hydrogen ion concentration Is 16 times 10 come the -8 Moller. Okay, so we'll execute the same thing we did critical time and collection that equal to ca and then again we're beginning with .64 moles for every one mole. But this time we're converting acid to base. So now we've just gained some math to execute so .26 .64 -1 over one plus X. Okay, just cross multiplying their we'll acquire 1.26 x correct 0.38. For this reason X is going come come out to it is in .30. So now our that's walk to it is in moles.

See more: Tucson To San Diego To Tucson Drive Time From San Diego, Ca To Tucson, Az

So now our percentage right, is We've convert .3 moles separated by the original, which to be .6 formals and multiply through 100. And we get that it will be 47 of ours H two p 04 minus is converted to h ns 04 come minus.