BRAINLIEST IF ANSWERED IN THE NEXT 5M

If the ionization constant of water, kw, at 40°c is 2.92 × 10-14, then what is the hydronium ion concentration and ph for an aci

charle [14.2K]

Answer is: the hydronium ion concentratio is 1.71×10⁻⁷ mol/dm³ and pH<6.76.

The Kw (the ionization constant of water) at 40°C is 2.94×10⁻¹⁴ mol²/dm⁶ or 2.94×10⁻¹⁴ M².

Kw = [H₃O⁺] · [OH⁻].

[H₃O⁺] = [OH⁻] = x.

Kw = x².

x = √Kw.

x = √2.94×10⁻¹⁴ M².

x = [H₃O⁺] = 1.71×10⁻⁷ M; concentration of hydronium ion.

pH = -log[H₃O⁺].

pH = -log(1.71×10⁻⁷ M).

pH = 6.76.

pH (potential of hydrogen) is a numeric scale used to specify the acidity or basicity an aqueous solution.

5 0

3 years ago

Read 2 more answers

What happens to a substance when it dissolves

uranmaximum [27]

Answer:

A solution is made when one substance called the solute "dissolves" into another substance called the solvent.

Explanation:

once it is broken down"dissolves" from bigger pieces it becomes much smaller groups

6 0

3 years ago

30.0L of helium gas into moles of helium gas.

zepelin [54]

<h3>Answer:</h3>

1.25 moles (R.T.P.) or 1.34 moles (S.T.P.)

<h3>Explanation:</h3>

1 mole of a gas occupies a volume of 24 liters at room temperature and pressure (R.T.P.)
On the other hand, 1 mole of a gas will occupy 22.4 Liters at standard temperature and pressure (S.T.P.)

Therefore, at R.T.P.

30.0 Liters will be equivalent to;

= 30.0 L ÷ 24 L

= 1.25 moles

At S.T.P

30.0 Liters will be equivalent to;

= 30.0 L ÷ 22.4 L

= 1.34 moles

Thus, 30.0 L of helium gas are equivalent to 1.25 moles of He at R.T.P. and 1.34 moles at S.T.P.

3 0

3 years ago

Determine the heat of reaction (ΔHrxn) for the combustion of ethanol (C2H5OH) by using heat of formation data: C2H5OH (l) + 3 O2

egoroff_w [7]

Answer:

$\Delta H_{rxn}=-1234.782kJ$

Explanation:

$\Delta H_{rxn}=\sum [n_{i}\times \Delta H_{f}^{0}(product)_{i}]-\sum [n_{j}\times \Delta H_{f}^{0}(reactant_{j})]$

Where $n_{i}$ and $n_{j}$ are number of moles of product and reactant respectively (equal to their stoichiometric coefficient).

$\Delta H_{f}^{0}$ is standard heat of formation.

So, $\Delta H_{rxn}=[2mol\times \Delta H_{f}^{0}(CO_{2})_{g}]+[3mol\times \Delta H_{f}^{0}(H_{2}O)_{g}]-[1mol\times \Delta H_{f}^{0}(C_{2}H_{5}OH)_{l}]-[3mol\times \Delta H_{f}^{0}(O_{2})_{g}]$

or, $\Delta H_{rxn}=[2mol\times -393.509kJ/mol]+[3mol\times -241.818kJ/mol]-[1mol\times -277.69kJ/mol]-[3mol\times 0kJ/mol]$

or, $\Delta H_{rxn}=-1234.782kJ$

4 0

3 years ago

25.0 g of barium hydroxide is dissolved in 120.0g of water. What is the morality?

Vinvika [58]

Molarity: M = #moles of solute / liters of solution

# moles = mass / molar mass

Molar mass calculation

Barium hydroxide = Ba (OH)2

Atomic masses
Ba = 137.4 g/mol
O=16 g/mol
H=1 g/mol
Molar mass of Ba (OH)2 = 137.4 g/mol + 2*16g/mol + 2*1 g/mol = 171.4 g/mol

# mol = 25.0g/171.4 g/mol = 0.146 mol

For the volume of water use the fact that the density is 1g/ml., so 120 g = 120 ml = 0,120 liters.

M = 0.146mol / 0.120 liters = 1.22 mol/liter

3 0

4 years ago