Answer:
An elementary particle can be one of two groups: a fermion or a boson. Fermions are the building blocks of matter and have mass, while bosons behave as force carriers for fermion interactions and some of them have no mass. The Standard Model is the most accepted way to explain how particles behave, and the forces that affect them. According to this model, the elementary particles are further grouped into quarks, leptons, and gauge bosons, with the Higgs boson having a special status as a non-gauge boson.
Answer:
oxygen is limiting reactant
Explanation:
Given data:
Mass of hydrogen = 16.7 g
Mass of oxygen = 15.4 g
Limiting reactant = ?
Solution:
Chemical equation:
2H₂ + O₂ → 2H₂O
Number of moles of hydrogen:
Number of moles = mass/ molar mass
Number of moles = 16.7 g/ 2 g/mol
Number of moles = 8.35 mol
Number of moles of oxygen:
Number of moles = mass/ molar mass
Number of moles = 15.4 g/ 32 g/mol
Number of moles = 0.48 mol
Now we will compare the moles of both reactant with product,
H₂ : H₂O
2 : 2
8.35 : 8.35
O₂ : H₂O
1 : 2
0.48 : 2×0.48 = 0.96 mol
The number of moles of water produced by oxygen are less so it will limiting reactant.
The correct answer is (A) from 2nd to 3rd shell.
The explanation :
when a gain of energy is the shift of the electrons from a shell of low energy to the shell of high energy
and we have here 2nd shell is the shell of low energy, and 3rd shell is the shell of high energy.
∴ (A) from 2nd to 3rd shell is the correct answer.
Answer:
a. 7.8*10¹⁴ He⁺⁺ nuclei/s
b. 4000s
c. 7.7*10⁸s
Explanation:
I = 0.250mA = 2.5 * 10⁻³A
Q = 1.0C
1 e- contains 1.60 * 10⁻¹⁹C
But He⁺⁺ Carrie's 2 charge = 2 * 1.60*10⁻¹⁹C = 3.20*10⁻¹⁹C
(A).
No. Of charge per second = current passing through / charge
1 He⁺⁺ = 2.50 * 10⁻⁴ / 3.2*10⁻¹⁹C
1 He⁺⁺ = 7.8 * 10¹⁴ He⁺⁺ nuclei
(B).
I = Q / t
From this equation, we can determine the time it takes to transfer 1.0C
I = 1.0 / 2.5*10⁻⁴ = 4000s
(C).
Time it takes for 1 mol of He⁺⁺ to strike the target =?
Using Avogadro's ratio,
1.0 mole of He = (6.02 * 10²³ ions/mol ) * (1 / 7.81*10¹⁴ He ions)
Note : ions cancel out leaving the value of the answer in mols.
1.0 mol of He = 7.7 * 10⁸s