The equation for the pH of a substance is pH = –log[H+], where H+ is the concentration of hydrogen ions. A basic solution has a pH of 11.2. An acidic solution has a pH of 2.4. What is the approximate difference in the concentration of hydrogen ions between the two solutions? a) 1.610^-9 b) 4.010^-3 c)6.710^-1 D)1.610^-1
PH=-log[H⁺]
First solution:
PH=11.2
11.2=-log[H⁺]
log[H⁺]=-11.2
[H⁺]=10⁻¹¹.²=6.0309⁻¹²
Second solution:
PH=2.4
2.4=-log[H⁺]
log[H⁺]=-2.4
[H⁺]=10⁻².⁴=3.9810⁻³
Difference between the two solutions=3.9810⁻³ - 6.0310⁻¹²≈4.010⁻³.
Answer: b) 4.0*10⁻³
Answer:
The correct answer si option (b).
Explanation:
\(pH = -\log[H+]\)
Concentration of hydrogen ions when pH is 11.2.
\(11.2=-\log[H^+]\)
\([H^+]=6.309\times 10^{-12} M\)
Concentration of hydrogen ions when pH is 12.4.
\(2.4=-\log[H^+]\)
\([H^+]'=0.0039810 M=3.9810\times 10^{-3} M\)
Difference between the hydrogen ions:
\(=[H^+]'-[H^+]\)
\(=0.00398 M-6.309\times 10^{-12} M=0.00397 M=3.97\times 10^{-3}\approx 4.0\times 10^{-3}M\)
Hence, the correct answer si option (b).