Buffers - mixtures of conjugate acid and conjugate base at ±1 pH unit from pH = pKa. Resistant to changes in pH in response to small additions of H+ or OH-. ... Polyprotic acids - dissociation of each H+ can be treated separately if the pKa values are different

3 0

2 years ago

When you use a crowbar to lift a large rock, you are working against the force called

Ne4ueva [31]

Gravity. The rock is being pushed down and you are counteracting that force with a crowbar pushing it upward.

7 0

2 years ago

When 70.4 g of benzamide (C7H7NO) are dissolved in 850. g of a certain mystery liquid X, the freezing point of the solution is 2

Arlecino [84]

Answer:

1.62

Explanation:

From the given information:

number of moles of benzamide $=\dfrac{70.4 \ g}{121.14 \ g/mol}$

= 0.58 mole

The molality = $\dfrac{mass \ of \ solute (i.e. \ benzamide )}{mass \ of \ solvent }$

$= \dfrac{0.58 }{0.85 }$

= 0.6837

Using the formula:

$\mathbf {dT = l \times k_f \times m}$

where;

dT = freezing point = 27

l = Van't Hoff factor = 1

kf = freezing constant of the solvent

∴

2.7 °C = 1 × kf × 0.6837 m

kf = 2.7 °C/ 0.6837m

kf = 3.949 °C/m

number of moles of NH4Cl = $\dfrac{70.4 \ g}{53.491 \ g /mol}$

= 1.316 mol

The molality = $\dfrac{1.316 \ mol}{0.85 \ kg}$

= 1.5484

Thus;

the above kf value is used in determining the Van't Hoff factor for NH4Cl

i.e.

9.9 = l × 3.949 × 1.5484 m

$l = \dfrac{9.9}{3.949 \times 1.5484 \ m}$

l = 1.62

5 0

2 years ago

The carbon dioxide gas that was generated during this reaction was collected at 295K and 125 kPa. If 43.2 L of carbon dioxidegas

Vladimir [108]

Answer:

The balanced equation for this reaction is C2H2 + 502 + 4H2O + 3C02. What volume of carbon dioxide is produced when 2.8 L of oxygen are consumed? 25Explanation:

8 0

2 years ago