All categories

2 years ago

Calculate the concentration of an aqueous solution of ca(oh)2 that has a ph of 11.30.

1 answer:

3 0

Answer:
[OH]- = 501.187 M

Explanation:
First, the given Ca(OH)2 is a base and not an acid. Therefore, we cannot do the calculations based on the pH vale. We need to get the pOH value.
pH + pOH = 14
11.3 + pOH = 14
pOH = 14 - 11.3 = 2.7

Now, pOH is calculated as follows:
pOH = -log [OH]
This means that:
2.7 = - log [OH]
[OH]- = 10^(2.7)
[OH]- = 501.187 M

Hope this helps :)

You might be interested in

The following reaction shows calcium chloride reacting with silver nitrate.

adell [148]

Grams of Ca(NO₃)₂ produced : 0.985 g

<h3>Further explanation</h3>

A reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reagents and products.

Reaction

CaCl₂ + 2AgNO₃ → 2AgCl + Ca(NO₃)₂

MW AgNO₃ : 107.9+14+3.16=169.9

mol AgNO₃ :

$\tt \dfrac{2}{169.9}=0.012$

mol ratio Ca(NO₃)₂ : AgNO₃ = 1 : 2, so mol Ca(NO₃)₂ :

$\tt \dfrac{1}{2}\times 0.012=0.006$

MW Ca(NO₃)₂ : 40.1+2.14+6.16=164.1 g/mol

mass Ca(NO₃)₂ :

$\tt 0.006\times 164.1=0.985$

7 0

2 years ago

g The reaction; 4 Ag(s) + O2(g) ----> 2 Ag2O(s), is exothermic. Which statement about the reaction is correct? (A) It is spon

melomori [17]

Answer:

The correct answer is B. It is spontaneous only at low temperatures.

Explanation:

In thermodynamics, the Gibbs free energy is a thermodynamic potential that can be used to calculate the maximum of reversible work that may be performed by a thermodynamic system at a constant temperature and pressure.

The spontaneity of a reaction is given by the equation:

ΔG = ΔH - TΔS

where:

ΔH: enthalpy variation

T: absolute temperature

ΔS: entropy variation

As the reaction is exothermic, ΔH<0

As the reaction order increases (the reagents are solid and gas and their product is solid), ΔS<0

Therefore, the reaction will be spontaneous when ΔG is negative.

ΔG = ΔH - TΔS

That is, the entropy term must be smaller than the enthalpy term.

Hence, the reaction will be spontaneous only at low temperatures.

4 0

2 years ago

2NOCl(g) ↔ 2NO(g) + Cl2(g) with K = 1.6 x10–5. In an experiment, 1.00 mole of pure NOCl and 1.00 mole of pure Cl2 are placed in

poizon [28]

Answer: $3.8\times 10^{-3}M$

Explanation:

Moles of $NOCl$ = 1 mole

Moles of $Cl_2$ = 1 mole

Volume of solution = 1 L

Initial concentration of $NOCl$ = 1 M

Initial concentration of $Cl_2$ = 1 M

The given balanced equilibrium reaction is,

$2NOCl(g)\rightleftharpoons 2NO(g)+Cl_2(g)$

Initial conc. 1 M 0M 1 M

At eqm. conc. (1-2x) M (2x) M (1+x) M

The expression for equilibrium constant for this reaction will be,

$K_c=\frac{[NO]^2[Cl_2]}{[NOCl]^2}$

The $K_c$ = $1.6\times 10^{-5}}$

Now put all the given values in this expression, we get :

${1.6\times 10^{-5}}=\frac{(2x)^2\times (1+x)}{(1-2x)^2}$

By solving the term 'x', we get :

$x=0.0019$

Concentration of $NO$ at equilibrium= (2x) M = $2\times 0.0019=3.8\times 10^{-3}M$

6 0

2 years ago

Which term refers to an electrochemical cell that uses a spontaneous redox reaction to produce an electric current?

umka21 [38]

Answer:

voltaic cell

Explanation:

3 0

2 years ago

Read 2 more answers

Which incorrect aspect of Rutherford’s model was fixed by Bohr’s model?

dolphi86 [110]

Answer:

Some things that were wrong with Rutherford's model were that the orbiting electrons should give off energy and eventually spiral down into the nucleus, making the atom collapse. Bohr proposed his quantized shell model of the atom to explain how electrons can have stable orbits around the nucleus. To remedy the stability problem, Bohr modified the Rutherford model by requiring that the electrons move in orbits of fixed size and energy.

Explanation:

7 0

2 years ago