document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=614192>Question 614192</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have a problem requiring me to find the value of p^H using the value of [H^+] by using the formula <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+pH+=+-log%28H%29+ ALIGN=MIDDLE  ALT=\"+pH+=+-log%28H%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Similarly, I have another problem requiring me to find the value of [H^+] by using pH.\r<BR>\n" );
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document.write( "I'll put these two problems to show what I mean.\r<BR>\n" );
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document.write( "1. Determine the p^H given the following value:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28H%29+=+1.58+%2A+10%5E-9+ ALIGN=MIDDLE  ALT=\"+%28H%29+=+1.58+%2A+10%5E-9+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "2. Determine the [H+] from the following pH value:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+pH+=+3.3+ ALIGN=MIDDLE  ALT=\"+pH+=+3.3+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "I figured that the first question's answer was 9, but it was actually 8.8, I'm guessing that's because of the 1.58, however I don't see how to use 1.58 to help find the answer.\r<BR>\n" );
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document.write( "Another thing troubling me about these is, that I don't understand logarithms very much, so I don't understand the process used to solve the problems.\r<BR>\n" );
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document.write( "Thanks in advance. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #386453 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=386453\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a logarithm is an exponent that some base must be raised to, to equal some value<BR>\n" );
document.write( "___ the base for \"common\" logarithms is 10 (logs are common unless otherwise indicated)\r<BR>\n" );
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document.write( "when quantities are multiplied, their logs are added<BR>\n" );
document.write( "___ when divided, the logs are subtracted\r<BR>\n" );
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document.write( "log(a) = b means 10^b = a\r<BR>\n" );
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document.write( "1.  log[H+] = log(1.58) + log(10^-9)\r<BR>\n" );
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document.write( "log[H+] = .199 + -9 = -8.801\r<BR>\n" );
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document.write( "pH = - log[H+] = - -8.801 = 8.8\r<BR>\n" );
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document.write( "2. - log[H+] = 3.3\r<BR>\n" );
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document.write( "log[H+] = - 3.3 = .7 - 4  (the log of the coefficient is less than one, while the exponent is an integer))\r<BR>\n" );
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document.write( "[H+] = 10^.7 * 10^-4 = 5.012 * 10^-4 </SPAN>\n" );
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