All categories

2 years ago

Calculate the ph of a 0.20 m solution of iodic acid (hio3, ka = 0.17).

1 answer:

7 0

Iodic acid partially dissociates into H+ and IO3-
Assuming that x is the concentration of H+ at equilibrium, and sine the equation says the same amount of IO3- will be released as that of H+, its concentration is also X. The formation of H+ and IO3- results from the loss of HIO3 so its concentration at equilibrium is 0.20 M - x
Ka = [H+] [IO3-] / [HIO3];
Initially, [H+] ≈ [IO3-] = 0 and [HIO3] = 0.20; 
At equilibrium [H+] ≈ [IO3-] = x and [HIO3] = 0.20 - x; 
so 0.17 = x² / (0.20 - x); 
Solving for x using the quadratic formula: 
x = [H+] = 0.063 M or pH = - log [H+] = 1.2.

You might be interested in

A precipitate of zinc hydroxide can be formed using the reaction below.

worty [1.4K]

Answer:

Option B is correct. KOH is the limiting reagent, and 0.27 mole of Zn(OH)2 precipitate is produced.

Explanation:

Step 1: Data given

Number of moles ZnCl2 = 0.36 moles

Number of moles KOH = 0.54 moles

Step 2: The balanced equations

ZnCl2(aq) + 2 KOH(aq) → Zn(OH)2(s) + 2 KCl(aq)

For 1 mol ZnCl2 we need 2 moles KOH to produce 1 mol Zn(OH)2 and 2 moles KCl

Step 3: Calculate the limiting reactant.

KOH is the limiting reactant. It will completely be consumed (0.54 moles). ZnCl2 is in excess. There will react 0.54/2 = 0.27 moles

There will remain 0.36 - 0.27 = 0.09 moles.

Step 4: The products

There will be produced 2 moles KCl and 1 mol Zn(OH)2. Zn(OH)2 is the precipitate produced.

For 1 mol ZnCl2 we need 2 moles KOH to produce 1 mol Zn(OH)2 and 2 moles KCl

For 0.54 moles KOH, we will produce 0.27 moles precipitate (Zn(OH)2)

Option A is not correct because 0.27 mol of Zn(OH)2 will precipitate, not 0.54 mol

Option B is correct

Option C is not correct because ZnCl2 is not the limiting reactant, but the excess reactant

Option D is not correct because ZnCl2 is not the limiting reactant, but the excess reactant

7 0

2 years ago

a metal worker uses a cutting torch that operates by reacting acetylene gas, C2H2(g), with oxygen gas, O2(g), as shown in the un

harkovskaia [24]

Answer:

650 grams

Explanation:

Given that acetylene gas reacts with oxygen to produce caobon dioxide, water and heat and the unbalnced equation is

$C_2H_2(g)+O_2(g) \rightarrow CO_2(g) + H_2O(g)+ heat$

Gram-formula mass of $C_2H_2= 26$ g/mol

So, mass of 1 mole of acelylene is 26 grams

Therefore, mass of 25 moles of acelylene=25x26=650 grams

Hence, the mass of 25 moles of acelylene is 650 grams

8 0

2 years ago

Read 2 more answers

If you find that the hydrogen alpha line in a star’s spectrum occurs at a wavelength of 656.45 nm, what is the star’s approximat

Paladinen [302]

Answer:

The answer to the question is

The star’s approximate radial velocity is 68.52 km/s

Explanation:

To solve the

The formula is

$\frac{\lambda-\lambda_{rw}}{\lambda_{rw}} = \frac{v_r}{c}$ where

$v_r$ = velocity of the star

λ = Star's spectrum wavelength = 656.45 nm

$\lambda_{rw}$ = Rest wavelength = 656.30 nm

c = Speed of light = 299 792 458 m / s

Therefore we have

$\frac{656.45-656.30}{656.30} =\frac{v_r}{299 792 458}$ or $v_r$ = 68518.7699 m/s or 68.52 km/s

8 0

2 years ago

When hydrogen chloride ionizes in water, which reactant is the proton donor? chlorine which reactant is the proton acceptor? hyd

AlladinOne [14]

Let's write the reaction first.

HCl + H₂O ---> H₃O⁺ + Cl⁻

These reaction has two reactants, either the proton donor or the proton acceptor. Water is amphoteric, meaning it can act as an acid or base. Since HCl is an acid, then water in this reaction acts as a base.

1. The proton donor is HCl because it donates H+ to water which yields a hydronium ion, H₃O⁺.
2. The proton acceptor is water.

5 0

2 years ago

If the reaction shown below is exothermic, the energy level of the reactants is ________. h2 + o2 → 2h2o

never [62]

An exothermic reaction is one which is accompanied by the release of heat energy.

In the given situation, hydrogen and oxygen combine to form water along with the generation of heat.

2H2 + O2 → 2H2O + heat

Based on the law of conservation of energy: 'energy can be neither created nor destroyed". This implies that whatever energy is released must have been present in the reactants. Therefore, the reactants must be in a higher energy level than products.

If the reaction shown below is exothermic, the energy level of the reactants is higher than products.

5 0

2 years ago