Answer: -
12.59
Explanation: -
Strength of NaOH = 0.0179 M
Volume of NaOH = 58.0 mL = 58.0/1000 = 0.058 L
Number of moles = 0.0179 M x 0.058 L
= 1.04 x 10⁻³ mol
Mol of [OH⁻] given by NaOH = 1.04 x 10⁻³ mol
Strength of Ba(OH)₂ = 0.0294 M
Volume of Ba(OH)₂ = 60.0 mL = 60.0/1000 = 0.060 L
Number of moles = 0.0294 M x 0.060 L
= 1.76 x 10⁻³ mol
Mol of [OH⁻] given by Ba(OH)₂ =2 x 1.76 x 10⁻³ mol
Total [OH⁻] = 1.04 x 10⁻³ mol + 2 x 1.76 x 10⁻³ mol
= 4.56 x 10⁻³ mol
Total volume of the mixture = 58.0 + 60.0
= 118.0 mL
118.0 mL of the solution has 4.56 x 10⁻³ mol [OH⁻]
1000 mL of the solution has 
= 0.0386 mol
Using the relation
pOH = - log [OH-]
= - log 0.0386
= 1.41
Using the relation
pH + pOH = 14
pH = 14 - 1.41
= 12.59
all i know is that the formula for triangles is base times hight divided by two, so add in a number to replace the missing number, multiply it by 55 and divide the answer by two. hope this helps and i really hope you get it right! or that im right...
Given:
P = 123 kPa
V = 10.0 L
n = 0.500 moles
T = ?
Assume that the gas ideally, thus, we can use the ideal gas equation:
PV = nRT
where R = 0.0821 L atm/mol K
123 kPa * 1 atm/101.325 kPa * 10.0 L = 0.500 moles * 0.0821 Latm/molK * T
solve for T
T = 295.72 K<span />
The amount of Silicon left after 300 years is 75g
It is given that the initial amount of Si is 100 times decay is 300 years and the half-life of Silicon is 710 years.
The radioactive decay formula is given by,
A = A₀ x 2^(-t/h);
where;
A is the resulting amount after t time, Ao is the initial amt (t=0),t is the time of decay, and h is the half-life of the substance.
On substituting the values from the given we get,
A = 100x2^(-300/710)
A = 100 x 0.746112347
A = 74.6112347 grams left after 300 yrs
Therefore, the number of grams of silicon left after 300 years is 74.6112347g. This value could be rounded off to 75 grams as in the whole number
To know more about half-life, click below:
brainly.com/question/1160651
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