The molarity of hydroxide ions can be found using which formula

Which statement is correct regarding the reaction below? 3A + 2B yields C + 2D The rate of formation of D is twice the rate of d

Vedmedyk [2.9K]

Answer:

The correct statements are:

The rate of disappearance of B is twice the rate of appearance of C.

Explanation:

Rate of the reaction is a change in the concentration of any one of the reactant or product per unit time.

3A + 2B → C + 2D

Rate of the reaction:

$R=-\frac{1}{3}\times \frac{d[A]}{dt}=-\frac{1}{2}\times \frac{d[B]}{dt}$

$-\frac{1}{3}\times \frac{d[A]}{dt}=\frac{1}{1}\times \frac{d[C]}{dt}$

$-\frac{1}{3}\times \frac{d[A]}{dt}=\frac{1}{2}\times \frac{d[D]}{dt}$

The rate of disappearance of B is twice the rate of appearance of C.

$\frac{1}{1}\times \frac{d[C]}{dt}=-\frac{1}{2}\times \frac{d[B]}{dt}$

$2\times \frac{1}{1}\times \frac{d[C]}{dt}=-\frac{1}{1}\times \frac{d[B]}{dt}$

8 0

4 years ago

Read 2 more answers

Limiting Reactants—————-

denis-greek [22]

Answer:

21.8 grams.

Explanation:

Molar mass data from a modern periodic table:

Mg: 24.301;
O: 15.999.

How many moles of MgO will be produced if Mg is the limiting reactant?

Number of moles of Mg:

$\displaystyle n = \frac{m}{M} = \frac{16.3}{24.301} = 0.670644\;\text{mol}$ .

The ratio between the coefficient of Mg and that of MgO is 2:2. Two moles of Mg will make two moles of MgO. 0.670644 moles of MgO will be produced if Mg is the limiting reactant.

How many moles of MgO will be produced if O₂ is the limiting reactant?

Number of moles of O₂:

$\displaystyle n = \frac{m}{M} = \frac{4.33}{15.999} = 0.270642\;\text{mol}$ .

The ratio between the coefficient of O₂ and that of MgO is 1:2. One mole of O₂ will make two moles of MgO. $2\times 0.270642 = 0.541284\;\text{mol}$ of MgO will be produced if O₂ is in excess.

How many moles of MgO will be produced?

0.541284 is smaller than 0.670644. Only 0.541284 moles of MgO will be produced since O₂ will run out before all 16.3 grams of Mg is consumed.

What's the mass of 0.541284 moles of MgO?

Formula mass of MgO:

$24.301 + 15.999 = 40.300\;\text{g}\cdot\text{mol}^{-1}$ .

Mass of 0.541284 moles of MgO:

$m = n \cdot M = 0.541284\times 40.300 = 21.8\;\text{g}$ .

7 0

3 years ago

What fossil helped support Wegener's hypothesis of continental drift?

Dominik [7]

Answer:

Glossopteris

Explanation:

Glossopteris is a fossil fern that helped support Wegener's hypothesis.

Hope this helps! Have a great day!

3 0

3 years ago

You measure 2.34 g of K2Cr2O7 into a volumetric flask. You dilute the K2Cr2O7 with water to a volume of 250 mL. It takes 35.7 mL

natta225 [31]

Answer:

0.191M of Na₂C₂O₄ is the concentration of the original Na₂C₂O₄ solution

Explanation:

The reaction of potassium dichromate, K₂Cr₂O₇ with sodium oxalate, Na₂C₂O₄ in the presence of acid H⁺ is:

K₂Cr₂O₇ + 3Na₂C₂O₄ + 14H⁺ → 2Cr³⁺ + 6CO₂ + 7H₂O + 6Na⁺ + 2K⁺

<em>Thus, 1 mole of K₂Cr₂O₇ reacts with 3 moles of Na₂C₂O₄</em>

Moles of 2.34g of K₂Cr₂O₇ (Molar mass: 294.185g/mol):

2.34g K₂Cr₂O₇ ₓ (1mol / 294.185g) = 7.954x10⁻³ moles K₂Cr₂O₇

In 250mL = 0.250L:

7.954x10⁻³ moles K₂Cr₂O₇ / 0.250L = 0.0318M K₂Cr₂O₇

Moles in 35.7mL = 0.0357L of this solution are:

0.0357L ₓ (0.0318mol / L) = <em>1.136x10⁻³ moles K₂Cr₂O</em>₇ in solution. As 1 mole of K₂Cr₂O₇ reacts with 3 moles of Na₂C₂O₄, to titrate the moles of K₂Cr₂O₇ in solution you need:

1.136x10⁻³ moles K₂Cr₂O₇ × (3 moles Na₂C₂O₄ / 1 mole K₂Cr₂O₇) =

<em>3.408x10⁻³ moles of Na₂C₂O₄</em>

In 17.8mL = 0.0178L:

3.408x10⁻³ moles of Na₂C₂O₄ / 0.0178L =

<h3>0.191M of Na₂C₂O₄ is the concentration of the original Na₂C₂O₄ solution</h3>

<em />

3 0

3 years ago

Why is there such a large jump and ionization energy between the second and third ionization energy‘s for magnesium?

Romashka [77]

The second ionization energy of Mg is larger than the first because it always takes more energy to remove an electron from a positively charged ion than from a neutral atom. The third ionization energy of magnesium is enormous, however, because the Mg2+ ion has a filled-shell electron configuration.

5 0

3 years ago