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At what pH are the moles of acid and base equal?

mihalych1998 [28]

Answer:

7

Explanation:

(Note: for a strong acid and strong base titration the equivalence point is at a pH=7. This is because at this point you have equal moles of added base as acid in the original solution. Therefore at the equivalence point the solution has formed a neutral salt and the pH is 7).

5 0

3 years ago

Read 2 more answers

A species that is isoelectronic with the nitrate ion and hence would have the same shape is [1] [2] [3] [4] [5] sulphur trioxide

Bumek [7]

Answer:

[1] sulphur trioxide

Explanation:

Isoelectronic species have the same number of valence electrons.

Valence electrons in nitrate (NO₃⁻):

5e- (N) + (3 x 6e-)(3xO) + 1e- (charge) = 24e-

Valence electrons in sulphur trioxide (SO₃):

6e- (S) + (3 x 6e-)(3xO) = 24e-

Valence electrons in sulphite (SO₃²⁻):

6e- (S) + (3 x 6e-)(3xO) + 2e- (charge) = 26e-

Valence electrons in phosphine (PH₃):

5e- (P) + (3 x 1e-)(3xH) = 8e-

Valence electrons in water (H₂O):

6e- (O) + (2 x 1e-)(2xH) = 8e-

Valence electrons in chlorite (ClO₂⁻):

7e- (Cl⁻) + (2 x 6e-)(2xO) + 1e- (charge) = 20e-

The only species isoelectronic with nitrate is sulphur trioxide. Both have trigonal planar geoemetry.

8 0

3 years ago

What is the concentration of NaCl in a solution if titration of 15.00 mL of the solution with 0.2503 M AgNO3 requires 20.22 mL o

Nina [5.8K]

Answer:

The concentration of NaCl = 0.3374 M

Explanation:

Given :

Molarity of AgNO₃ = 0.2503 M

Volume of AgNO₃ = 20.22 mL

The conversion of mL into L is shown below:

$1 mL= 10^{-3} L$

Thus, volume of the solution = 20.22×10⁻³ L

Molarity of a solution is the number of moles of solute present in 1 L of the solution.

$Molarity=\frac{Moles\ of\ solute}{Volume\ of\ the\ solution}$

The formula can be written for the calculation of moles as:

$Molarity=\frac{Moles\ of\ solute}{Volume\ of\ the\ solution}$

Thus,

$Moles\ of\ AgNO_3 =Molarity \times {Volume\ of\ the\ solution}$

$Moles\ of\ AgNO_3 =0.2503 \times {20.22\times 10^{-3}}\ moles$

$Moles\ of\ AgNO_3 = 5.0611 \times 10^{-3} moles$

The chemical reaction taking place:

$AgNO_3_(aq) + NaCl_(aq) \rightarrow AgCl_(s) + NaNO_3_(aq)$

According to reaction stoichiometry:

1 mole of AgNO₃ reacts with 1 mole of NaCl

Thus,

5.0611×10⁻³ moles of AgNO₃ reacts with 5.0611×10⁻³ moles of NaCl

Thus, moles of NaCl required = 5.0611×10⁻³ moles

Volume of NaCl required = 15.00 mL

The conversion of mL into L is shown below:

$1 mL= 10^{-3} L$

Thus, volume of the solution = 15.00×10⁻³ L

Applying in the formula of molarity as:

$Molarity=\frac{Moles\ of\ solute}{Volume\ of\ the\ solution}$

$Molarity\ of\ NaCl=\frac{5.0611\times 10^{-3}}{15.00\times 10^{-3}}$

$Molarity\ of\ NaCl= 0.3374 M$

Thus, the concentration of NaCl = 0.3374 M

6 0

3 years ago

The atomic number of sodium (Na) is 11. This is also the number of which of the following?

attashe74 [19]

D. Protons, Atomic number is the number of protons in an atom.

3 0

3 years ago

Which of the following is NOT true regarding Rutherford's Gold Foil experiment?

erastova [34]

Answer:

The area around the nucleus must be of low mass.

Explanation:

Rutherford`s experiment showed that there are some positive charges in the center of the atoms, and because they are all together, they will give a great mass to the atom.

It was quite different from Thomson`s experiment, in which it was thought that the negative charges were mixed with the positive charges, around the atom (like a Pudding Model). In Rutherford`s experiment, because the direction of beta particles, it was the prediction of the positive nucleus.

Hope this info is useful.

8 0

3 years ago