Explain why this substance is formed?

In a titration, 25.9 mL of 3.4 x10^-3 M Ba(OH)2 neutralized 16.6 mL of HCL solution. What is the molarity of the HCL solution?

san4es73 [151]

First, We have to write the equation for neutralization:
Ba(OH)2 + 2HCl → BaCl2 + 2H2O
so, from the equation of neutralization, we can get the ratio between Ba(OH)2 and HCl. Ba(OH)2 : HCl = 1:2
- We have to get the no.of moles of Ba(OH)2 to do the neutralization as we have 25.9ml of 3.4 x 10^-3 M Ba(OH)2.
So no.of moles of Ba(OH)2 = (25.9ml/1000) * 3.4x10^-3 = 8.8 x 10^-5 mol
and when Ba(OH)2 : HCl = 1: 2
So the no.of moles of HCl = 2 * ( 8.8x10^-5) = 1.76 x 10^-4 mol

So when we have 1.76X10^-4 Mol in 16.6 ml (and we need to get it per liter)
∴ the molarity = no.of moles / mass weight
= (1.76 x 10^-4 / 16.6ml)* (1000ml/L) = 0.0106 M Hcl

4 0

3 years ago

1 Select the correct answer! Which statement best explains the octet rule? A. Atoms gain, lose, or share electrons to achieve a

Ostrovityanka [42]

Answer:

A. Atoms gain, lose, or share electrons to achieve a full valence shell

Explanation:

The octet rule is best explained as the process in which atoms lose or gain or share electrons to achieve a full valence shell.

In this process bonds are formed when there is an attraction between the two substances.
For electrovalent compounds, an atom will lose electrons or gain electron to form an ion, the electrostatic attraction causes the bond formation.
Covalent compounds, form by sharing of electrons.

Therefore, the octet rule is attained when atoms gain full valence configuration.

5 0

3 years ago

1. From the following standard electrochemical potential (and your knowledge of biomedically important metals), answer the quest

Monica [59]

Answer:

The following answer are based only on emf values

a).Most anodic element ,Titanium - Ti

b).Metal That will corrode easily is : Titanium - Ti

c). Most reactive metal is Titanium-Ti

d).Al can't be used for making implants because it undergo corrosion easily and do not form strong passive oxide layer.

Ti forms very strong passive layer which prevents further corrosion.

Au is least reactive and does not corrode.

Note : You have to give answer according to E values

In actual(without considering E values) most anodic, reactive , corrosive element is Al

Explanation:

Here the oxidation potential data is given (since elements are getting oxidised)

$\Delta^{0} E$ : Standard Reduction Potential : It is tendency of the element to gain electron and get reduced.

Oxidation Potential is opposite to reduction potential

Standard Oxidation Potential :It is tendency of the element to loose electron and get oxidised.

It is measured in Volts/V

More positive (greater)the value of the oxidation potential , stronger is the tendency of the element to get oxidised.
More negative(lesser) the value of oxidation potential lesser the tendency of the element to get oxidised. Hence the element undergo Reduction in comparison to other with more positive value .

The main application $\Delta^{0} E$ values is in electrochemical cell to predict the products of the reaction. or predict whether the reaction is spontaneous or not.

Anodic means tendency to undergo oxidation

Since $Ti\rightarrow Ti^{+}$ has maximum value of $\Delta^{0}E$ = 2.00V , so it get oxidised as compared to other elements.

Corrode , The metal which oxidise easily will also undergo corrosion easily

From the , E values Ti show maximum tendency of oxidation hence it also get corroded easily.

Ti is the most reactive because it oxidised fast as compare to other elements
Au (gold) is the least reactive element as its $\Delta^{0}E$ value is negative. So gold don't get corrode and used for making implants. Ti can also be used , since it is most reactive so it react with oxygen present in atmosphere and form a passive layer of oxide which prevent its corrosion. Al also form passive oxide but form very thin layer which is not able to protect it from corrosion

4 0

4 years ago

Calcium hydride (cah2) reacts with water to form hydrogen gas: cah2(s) + 2h2o(l) → ca(oh)2(aq) + 2h2(g) how many grams of cah2 a

andreev551 [17]

Using the ideal gas law equation, we can find the number of H₂ moles produced.
PV = nRT
Where P - pressure - 0.811 atm x 101 325 Pa/atm = 82 175 Pa
V - volume - 58.0 x 10⁻³ m³
R - universal gas constant - 8.314 Jmol⁻¹K⁻¹
T - temperature - 32 °C + 273 = 305 K
substituting these values in the equation,
82 175 Pa x 58.0 x 10⁻³ m³ = n x 8.314 Jmol⁻¹K⁻¹ x 305 K
n = 1.88 mol

The balanced equation for the reaction is as follows;
CaH₂(s) + 2H₂O(l) --> Ca(OH)₂(aq) + 2H₂(g)
stoichiometry of CaH₂ to H₂ is 1:2
When 1.88 mol of H₂ is formed , number of CaH₂ moles reacted = 1.88/2 mol
therefore number of CaH₂ moles reacted = 0.94 mol
Mass of CaH₂ reacted - 0.94 mol x 42 g/mol = 39.48 g of CaH₂ are needed

3 0

3 years ago

For a gaseous carbon atom in its' ground state which of the following are possible sets of quantum numbers for two different ele

MAXImum [283]

Answer:

Option e=>

electron 1; n l ml ms = 2 1 0 +1/2.

electron 2;n l ml ms= 2 1 -1 +1/2.

Explanation:

The electronic configuration of carbon in its ground state is 1s2 2s2 2p2. The excited electronic configuration of carbon is given as; 1s2 2s1 2p3 because one of the electrons moves to the 2p sub- orbital because of the absorption of the atom.

Recall that there are four different types of quantum numbers and they are the principal quantum number,n; the Azimuthal quantum number, l; the magnetic quantum number, ml and the spin quantum number, Ms.

Our principal quantum number,n is TWO(2) which is the highest energy level from the electronic configuration written above.

The Azimuthal quantum number is 1 from l= n - 1.

The magnetic quantum number is -1 and 0 because we have two electrons filling the 3 orbitals of 2p sublevels. That is;

2px = -1 , 2py = 0 and 2pz = +1.

Only 2px and 2py will be considered because we have 2 electrons on the 2p in the ground state electronic configuration.

Therefore, the first electron will have ml= 0 and the second electron will have ml= -1.

Spin quantum number, ms; in both electrons the spins is an up spin so we have a +1/2 for both electron.

Hence; electron 1; n l ml ms = 2 1 0 +1/2.

Electron 2;n l ml ms= 2 1 -1 +1/2.

8 0

3 years ago