When barium hydroxide and ammonium chloride react,the temperature of the mixture decreases.What kind of reaction is this?

What is the IUPAC name of the following compounds i. CO₂ ii. NO₂ iii. HNO3 iv. H₂SO4 v. K-Cr₂O vi. [Fe(CN)

Zielflug [23.3K]

Explanation:

I) carbon dioxide

ii) nitrogen dioxide

iii) nitric acid

iv) sulphric acid

v) Potassium dichromate

vi) hexacyanoferrate (III) ion( not sure)

8 0

2 years ago

Rank the following elements by effective nuclear charge, Zeff, for a valence electron. F LI Be B N

Stels [109]

Answer:

Rank in increasing order of effective nuclear charge:

Li < Be < B < N < F

Explanation:

This explains the meaning of effective nuclear charge, Zeff, how to determine it, and the calculations for a valence electron of each of the five given elements: F, Li, Be, B, and N.

1) Effective nuclear charge definitions

While the total positive charge of the atom nucleus (Z) is equal to the number of protons, the electrons farther away from the nucleus experience an effective nuclear charge (Zeff) less than the total nuclear charge, due to the fact that electrons in between the nucleus and the outer electrons partially cancel the atraction from the nucleus.

Such effect on on a valence electron is estimated as the atomic number less the number of electrons closer to the nucleus than the electron whose effective nuclear charge is being determined: Zeff = Z - S.

2) Z eff for a F valence electron:

F's atomic number: Z = 9
Total number of electrons: 9 (same numer of protons)
Period: 17 (search in the periodic table or do the electron configuration)
Number of valence electrons: 7 (equal to the last digit of the period's number)
Number of electrons closer to the nucleus than a valence electron: S = 9 - 7 = 2
Zeff = Z - S = 9 - 2 = 7

3) Z eff for a Li valence eletron:

Li's atomic number: Z = 3
Total number of electrons: 3 (same number of protons)
Period: 1 (search on the periodic table or do the electron configuration)
Number of valence electrons: 1 (equal to the last digit of the period's number)
Number of electrons closer to the nucleus than a valence electron: S = 3 - 1 = 2
Z eff = Z - S = 3 - 2 = 1.

4) Z eff for a Be valence eletron:

Be's atomic number: Z = 4
Total number of electrons: 4 (same number of protons)
Period: 2 (search on the periodic table or do the electron configuration)
Number of valence electrons: 2 (equal to the last digit of the period's number)
Number of electrons closer to the nucleus than a valence electron: S = 4 - 2 = 2
Z eff = Z - S = 4 - 2 = 2

5) Z eff for a B valence eletron:

B's atomic number: Z = 5
Total number of electrons: 5 (same number of protons)
Period: 13 (search on the periodic table or do the electron configuration)
Number of valence electrons: 3 (equal to the last digit of the period's number)
Number of electrons closer to the nucleus than a valence electron: S = 5 - 3 = 2
Z eff = Z - S = 5 - 2 = 3

6) Z eff for a N valence eletron:

N's atomic number: Z = 7
Total number of electrons: 7 (same number of protons)
Period: 15 (search on the periodic table or do the electron configuration)
Number of valence electrons: 5 (equal to the last digit of the period's number)
Number of electrons closer to the nucleus than a valence electron: S = 7 - 5 = 2
Z eff = Z - S = 7 - 2 = 5

7) Summary (order):

Atom Zeff for a valence electron

F 7

Li 1

Be 2

B 3

N 5

Conclusion: the order is Li < Be < B < N < F

6 0

3 years ago

The decomposition of hydrogen peroxide (H2O2(aq)) is proposed to follow a reaction mechanism of: Step 1: H2O2(aq) + Br–(aq)→H2O(

lys-0071 [83]

Answer:

Option (1) Br– is the catalyst, and the reaction follows a faster pathway with Br– than without

Explanation:

Let us consider the equation below:

Step 1:

H2O2(aq) + Br–(aq) → H2O(l) + BrO–(aq)

Step 2:

BrO–(aq) + H2O2(aq) → H2O(l) + O2(g) + Br–(aq)

From the above equation, we can see that Br– is unchanged.

This implies that Br– is the catalyst as catalyst does not take part in a chemical reaction but they create an alternate pathway to lower the activation energy in order for the reaction to proceed at a much faster rate to arrive at the products.

8 0

3 years ago

Classify the following reactions: HCl(aq)+NaOH(aq)→NaCl(aq)+H2O(l)HCl(aq)+NaOH(aq)→NaCl(aq)+H2O(l) Ba(OH)2(aq)+ZnCl2(aq)→BaCl2(a

Savatey [412]

The reactions are

HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)

Ba(OH)2(aq) + ZnCl2(aq) → BaCl2(aq) + Zn(OH)2(s)

2AgNO3(aq) + Mg(s) → Mg(NO3)2(aq) + 2Ag(s)

Answer:

HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l) = Acid-base reaction

Ba(OH)2(aq) + ZnCl2(aq) → BaCl2(aq) + Zn(OH)2(s) = Precipitation reaction

2AgNO3(aq) + Mg(s) → Mg(NO3)2(aq) + 2Ag(s) = Redox reaction

Explanation:

HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l) .

The reaction above is an example of an acid-base reaction. Acid-base reaction is a chemical reaction between an acid and a base. The product is usually a salt and water. An acid dissolves in water to produce H+ ion. Hydrochloric acid is a strong acid as it is completely dissociated in water. A base dissolves in water to form hydroxide ion(OH-). The sodium hydroxide is a strong base as it completely dissociate in water. The reaction between a base and an acid can be known as a neutralization reaction.

Ba(OH)2(aq) + ZnCl2(aq) → BaCl2(aq) + Zn(OH)2(s)

The reaction above is a precipitation reaction. Precipitation reaction is a reaction where two ionic bonds or cations and anions in an aqueous solution react to form an insoluble salts. The insoluble salt formed is known as the precipitate. The reaction above is an example of a double replacement reaction. From the equation the ions replace each other depending on the cations and anions. They switch partners as both reactants lose their partners to form new partnership with a different ion. The two reactants ( Ba(OH)2 and ZnCl2 ) are aqueous solution, they react to from a solid precipitates( Zn(OH)2(s) ).

2AgNO3(aq) + Mg(s) → Mg(NO3)2(aq) + 2Ag(s)

The reaction is known as an oxidation-reduction reaction(Redox reaction). A oxidation-reduction reaction their is a transfer of electron(s) between two species. The oxidation number of a chemical reaction changes by losing or gaining electrons. One of the reactant is a reducing agent and the other is an oxidizing agent.

From the reaction Mg is the reducing agent and AgNO3 is the oxidizing agents.

2 Ag+ + 2 e- → 2 Ag∧0 (reduction)

Mg∧0 - 2 e- → Mg²+ (oxidation)

8 0

3 years ago

Does data from mass spectrometry indicate that modern scientists have made modifications to Dalton''s model? Justify.

Gelneren [198K]

John Dalton was a scientist who proposed that all matter consists of atoms. At this stage, no one had yet discovered neutrons and the nucleus. As a result, Dalton's model consisted of a single atom i.e. the atom was the smallest object.
A mass spectrometer is an instrument that is able to see what is inside an atom. Scientists have been able to prove that the item is not the smallest object in the world. Atoms are made up of smaller objects called protons, neutrons and electrons.
We can, therefore, safely conclude that data from mass spectrometry has helped modern scientists to make modifications to Dalton's model.

5 0

3 years ago