This is an acid base reaction and the chemical equation for the above reaction is as follows;
KOH + HClO₄ ---> KClO₄ + H₂O
the stoichiometry of acid to base is 1:1
KOH is a strong base and HClO₄ is a strong acid therefore they both ionize completely into their respective ions
Number of KOH moles - 0.723 M/1000 mL/L x 25.0 mL = 0.018 mol
Number of HClO₄ moles - 0.273 M/1000 mL/L x 50 mL = 0.013 mol
since acid and base react completely, 0.013 mol of acid reacts with 0.013 mol of base.
The excess base remaining is - 0.018 - 0.013 = 0.005 mol
total volume of solution = 25.0 mL + 50.0 mL = 75.0 mL
[OH⁻] = 0.005 mol/0.075 L = 0.067 M
pOH = -log[OH⁻]
pOH = -log(0.067 M)
pOH = 1.17
pOH + pH = 14
Therefore pH = 14 - 1.17 = 12.83
by knowing pH we can calculate the [H₃O⁺]
pH = -log [H₃O⁺]
[H₃O⁺] = antilog[-12.83]
[H₃O⁺]= 1.47 x 10⁻¹³ M
Answer:Locate the row corresponding to known unit of torque along the left of the table. Multiply by the factor under the column for the desired units. For example, to convert 2 oz-in torque to n-m, locate oz-in row at table left. Locate 7.062 x 10-3 at intersection of desired n-m units column. Multiply 2 oz-in x (7.062 x 10-3 ) = 14.12 x 10-3 n-m.
Converting between units is easy if you have a set of equivalencies to work with. Suppose we wanted to convert an energy quantity of 2500 calories into watt-hours. What we would need to do is find a set of equivalent figures for those units. In our reference here, we see that 251.996 calories is physically equal to 0.293071 watt hour. To convert from calories into watt-hours, we must form a “unity fraction” with these physically equal figures (a fraction composed of different figures and different units, the numerator and denominator being physically equal to one another), placing the desired unit in the numerator and the initial unit in the denominator, and then multiply our initial value of calories by that fraction.
Explanation:
Since both terms of the “unity fraction” are physically equal to one another, the fraction as a whole has a physical value of 1, and so does not change the true value of any figure when multiplied by it. When units are canceled, however, there will be a change in units. For example, 2500 calories multiplied by the unity fraction of (0.293071 w-hr / 251.996 cal) = 2.9075 watt-hours.
E is Bohrs model the dots on the rings represent the valence electrons
Answer:
The molar concentration of this solution is 0.0463 mol/L
Explanation:
Step 1 : Data given
Mass of a nonelectrolyte solute = 2.69 grams
Volume of water = 345 mL = 0.345 L
Temperature = 26.0°CC = 273 + 26 = 299 K
The osmotic pressure = 863 torr
⇒ 863torr /760 = 1.13553 atm
Step 2: Calculate the molar concentration of this solution
Π = i*M*R*T
⇒with Π = the osmotic pressure = 1.13553 atm
⇒with i = the van't Hoff factor of the nonelectrolyte solute = 1
⇒with M = the molar concentration = TO BE DETERMINED
⇒with R = the gas constant = 0.08206 L*atm/mol*K
⇒with T = the temperature = 299 K
1.13553 atm = 1 * M * 0.08206 L*atm/mol*K * 299 K
M = 1.13553 / (0.08206*299)
M = 0.0463 mol/L
The molar concentration of this solution is 0.0463 mol/L
