54. fluorine
55. oxygen
56. they have the same number of protons
57. nucleus 3
Explanation:
54. The element represented by the nucleus 1 have 9 protons and 9 neutrons. The atomic number of the element is equal to the number of protons = 9, so the element is fluorine.
55. The element represented by the nucleus 2 have 8 protons and 10 neutrons. The atomic number of the element is equal to the number of protons = 8, so the element is oxygen.
56. nucleus 2 contains 8 protons and 10 neutrons
nucleus 4 contains 8 protons and 11 neutrons.
The atoms that have the same number of protons but different number of neutrons are called isotopes.
57. nucleus 3 have 10 protons and 10 neutrons and correspond to neon. Neon have 10 electrons (equal to the number of protons) and have the electronic configuration 1s² 2s² 2p⁸. Because all the electrons shells are filled with electrons, neon have a stable electron configuration.
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subatomic particles
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Answer:
The reflection of sound waves
Explanation:
An echo is a reflection of sound that bounces of of one thing to another.
Answer:
one-half
Explanation:
cuz for a first order reaction is a half life independent of concentration and constant over time
Answer:
Correct option is
B
5 liters of CH
4
(g)NO
2
at STP
No. of molecules=
22.4
5
mol=
22.4
5
×N
A
molecules
A) 5ℊ of H
2
(g)
No. of moles=
2
5
mol=
2
5
×N
A
molecules
B) 5l of CH
4
(g)
No. of moles of CH
4
=
22.4
5
mol=
22.4
5
N
A
molecules
C) 5 mol of O
2
=5N
A
O
2
molecules
D) 5×10
23
molecules of CO
2
(g)
Molecules of 5l NO
2
(g) at STP=5l of CH
4
(g) molecules at STP
Therefore, option B is correct.
Answer: Balanced molecular equation :
Total ionic equation:
The net ionic equation:
Explanation:
Complete ionic equation : In complete ionic equation, all the substances that are strong electrolyte are present in an aqueous state as ions.
Net ionic equation : In the net ionic equations, we are not include the spectator ions in the equations.
Spectator ions : The ions present on reactant and product side which do not participate in a reactions. The same ions present on both the sides.
When sodium phosphate and zinc acetate then it gives zinc phosphate and sodium acetate as product.
The balanced molecular equation will be,
The total ionic equation in separated aqueous solution will be,
In this equation, and are the spectator ions.
By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.
The net ionic equation will be,
