Calculate the energy of a photon emitted when an electron in a hydrogen atom undergoes a transition from =3 to =1.
Answer:
[tex]1.936\times 10^{-18}\ \text{J}[/tex]
Explanation:
[tex]R_h[/tex] = Rydberg constant = [tex]2.178\times 10^{-18}\ \text{J}[/tex]
[tex]n_i[/tex] = Initial shell = 3
[tex]n_f[/tex] = Final shell = 1
We have the relation
[tex]\Delta E=R_h(\dfrac{1}{n_f^2}-\dfrac{1}{n_i^2})\\\Rightarrow \Delta E=2.178\times 10^{-18}(\dfrac{1}{1^2}-\dfrac{1}{3^2})\\\Rightarrow \Delta E=1.936\times 10^{-18}\ \text{J}[/tex]
The energy of the photon emitted here is [tex]1.936\times 10^{-18}\ \text{J}[/tex].
2) Which liberates the most energy?
A) F(g) + e ➡️ F-(g)
B) N(g) +e- ➡️ N-(g)
C) O(g) +e ➡️ O-(g)
D) C(g) +e ➡️ C-(g)
Answer: [tex]F(g)+e^-\rightarrow F^-(g)[/tex]
Explanation:
Electron gain enthalpy is defined as energy released on addition of electron to an isolated gaseous atom.
The amount of energy released will be maximum when the tendency to attract electrons is maximum. As flourine has atomic number of 9 and has electronic configuration of 2,7. It can readily gain 1 electron to attain stable noble gas configuration and hence liberates maximum energy.
[tex]F(g)+e^-\rightarrow F^-(g)[/tex]
How many grams are there in 3.4 x 10^24 atoms of He?
Group of answer choices
2.07
5.7 g
0.57 g
20.7
Given :
Number of He atoms, [tex]n = 3.4\times 10^{24}[/tex] atoms.
To Find :
How many grams are their in given number of He atoms.
Solution :
We know, molecular mass of He is 4 g. It means that their are [tex]6.022 \times 10^{23}[/tex] atoms in 4 g of He.
Let, number of gram He in [tex]3.4\times 10^{24}[/tex] atoms is x , so :
[tex]x = \dfrac{3.4\times 10^{24}}{6.022\times 10^{23}}\times 4\\\\x = $$22.58\ g[/tex]
Therefore, grams of He atoms is 22.58 g .
5. If all the particles in a material are made up of
several smaller particles, and every larger particle
is identical, is the material a pure substance or
not? Explain your reasoning.
Answer:
No. Because a pure substance, no matter if an element, compound, it can only contain one kind of particle .
Explanation:
Suppose you have a mixture of iron filings, sand, and sugar and you want to separate the three. Fill in the materials you expect to see at each step as you perform the actions shown to separate them. The materials you may expect to see are: iron filings, sand, sugar, and sugar water.
Answer:
Explanation:
mixture of iron filings, sand, and sugar
First Step - Iron Fillings
Use a magnet to separate the iron fillings from the mixture. Due to magnetic properties of the iron fillings, the magnets would attract the iron fillings and separate it from the mixture.
Second step - Sand
Place the sand and sugar mixture in water. The sugar would dissolve in water and the sand easily separated by filtration.
Third step - Sugar and Sugar water
Boil the sugar water to remove the water and place in the refrigerator for crystallization of the sugar.
I gave brainlest:: answer this .....
2
Convert -27°C to Kelvin.
Answer:
-27 C converted to Kelvin is 246.15 Kelvin.
Explanation:
Hope this helps
Answer:
246.15K
Explanation:
Formula: (-27°)C + 273.15 = 246.15K
element A it's valance number is 3 and element B it's valance number is 6 make it compound
Answer:
A2B
Explanation:
A = 3
B = 6
exchange valencies
A6B3
A2B
A __________________ chemical equation shows that the same number of atoms in the reactants are also in the product.
balanced
rearranged
transferred
beautiful
Heat from the sun moves through space by the process of
es
A)
circulation.
B)
conduction
C)
convection.
D)
radiation
with 24.1 moles of P4O10 how many moles of H3PO4 could be made
whats the balance to Sr + O, SrO
Answer:
SrO = Sr + O - Chemical Equation Balancer.
Explanation:
How much heat is released when 24.8 g of ch4 is burned in excess oxygen gas?
The given question is incomplete. The complete question is:
How much heat is produced when 24.8 g of [tex]CH_4[/tex] is burned in excess oxygen gas
Given: [tex]CH _4 +2O_2\rightarrow CO_2+2H_2O[/tex] ΔH= −802 kJ.
Answer: 1243.1 kJ
Explanation:
Heat of combustion is the amount of heat released on complete combustion of 1 mole of substance.
Given :
Amount of heat released on combustion of 1 mole of methane = 802 kJ kJ/mol
According to avogadro's law, 1 mole of every substance occupies 22.4 L at NTP, weighs equal to the molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
1 mole of [tex]CH_4[/tex] weighs = 16 g
Thus we can say:
16 g of [tex]CH_4[/tex] on combustion releases heat = 802 kJ
Thus 24.8 g of [tex]CH_4[/tex] on combustion releases =[tex]\frac{802}{16}\times 24.8=1243.1kJ[/tex]
Thus heat released when 24.8 g of methane is burned in excess oxygen gas is 1243.1 kJ
Identify the products in the reaction HCI + NaOH → NaCl + H20.
A. HCI, NaOH, NaCl, and H2O
B. HCl and NaOH
C. NaCl and H20
D. NaOH and H20
The products in the reaction HCI + NaOH → NaCl + H20, are C. NaCl and H20.
How are these the products ?The reaction between hydrochloric acid (HCl) and sodium hydroxide (NaOH) is a neutralization reaction, which means that it produces a salt and water. In this case, the salt is sodium chloride (NaCl) and the water is H2O.
The other options are not correct because they do not include all of the products of the reaction. Option (A) includes HCl and NaOH, but it does not include H2O. Option (B) only includes HCl and NaOH. Option (D) only includes NaOH and H2O.
In conclusion, option C is correct.
Find out more on products at https://brainly.com/question/20322602
#SPJ6
An increase in the volume of a substance because of an increase in temperature is called
Answer:
Its called contraction.
Explanation:
What is the amount of diamine silver that can be formed when 10.00 g AgCl is mixed with 1.00 L of 0.100 M NH3?
The amount of diamine silver chloride = 8.87 g
Further explanationGiven
10 g AgCl
1.00 L of 0.100 M NH3
Required
the amount of diamine silver
Reaction
AgCl + 2 NH₃ → [Ag(NH₃)₂]Cl
mol AgCl :
= mass : MW
= 10 g : 143,32 g/mol
= 0.0698
mol NH₃ :
= M x V
= 0.1 x 1
= 0.1
NH₃ as a limiting reactant
mol [Ag(NH₃)₂]Cl based on NH₃ :
= 1/2 x mol NH₃
= 1/2 x 0.1
= 0.05
Mass diamine silver :
= 0.05 x 177.3822 g/mol
= 8.87 g
13.Which shows the order of increasing ionization energy?
a.Si, Al, Mg, Na
b.Ga, Ge, As, Se
c.Be, Mg, Ca, Sr
d.F, Cl, Br, I
1.a)concentrated sulphuric acid reacts with ethanol to produce ethene
(i) state the conditions for the reaction
.......................................................................
write the equation of the leads to formation of ethene In (a) (i) above.
.....................................................................................
state the property of sulphuric acid shown in reaction (a)(ii)
...................................................................................
Answer: a) Temperature of [tex]170^0C[/tex]
b) [tex]C_2H_5OH\stackrel{conc H_2SO_4, 170^0C}\rightarrow C_2H_4+H_2O[/tex]
c) dehydrating agent
Explanation:
Ethanol is heated with an excess of concentrated sulfuric acid at a temperature of 170°C to produce ethene.
The balanced chemical reaction is:
[tex]C_2H_5OH\stackrel{conc H_2SO_4, 170^0C}\rightarrow C_2H_4+H_2O[/tex]
Here concentrated sulfuric acid removes a water molecule from ethanol and thus acts as a dehydrating agent.
answers this...i gave brainlest!!
Answer:
I hope I can help
Explanation:
I hope I can help you
1 point
If the element Lithium (Li) were to bond with the element Sulfur (s), what
type of bond can you predict will be formed and why?*
A. Covalent-Li and S are two nonmetals
B. Covalent-Li is a metal and S is a nonmetal
C. Ionic-Li and S are two nonmetals
D. Ionic-Li is a metal and S is a nonmetal
Answer:
C. Ionic-Li and S are two nonmetals