Answer:
Explanation:
1. Atomic numbers:
Atomic number is the number of protons in an atom. It is one of the most diagonistic and representative number used in identifying an atom. The periodic table of element arranges elements based on this number.
No two elements have the same atomic number.
Protons are positively charged particles in an atom.
- In a neutral atom, the atomic number is the same as the number electrons since electrical neutrality is attained when the number of protons and electrons are the same.
- The atomic number determines the position of an atom on the periodic table and it is unique for every atom.
2.
Periodic patterns
These are trends on that can be predicted on the periodic table because they shew regularities down a group or sometimes across the period.
Some of these trends are atomic radius, electronegativity, metallicity, nuclear charge e.t.c
Properties of elements can be predicted using these patterns even before they are discovered.
b.
Physical property shared by Helium, Argon and Neon is that they are all gases. All group 8 elements are called noble or inert gases.
Chemical property of these elements: they are chemically unreactive.
These gases are very stable having complete electronic shell configuration. Every atom on the periodic table tries to attain the state of the noble gases.
C.
Noble Gases/ Inert Gases/ Group O elements
The relative molecular mass of the gas : 64 g/mol
<h3>Further explanation</h3>
Given
Helium rate = 4x an unknown gas
Required
The relative molecular mass of the gas
Solution
Graham's Law
r₁=4 x r₂
r₁ = Helium rate
r₂ = unknown gas rate
M₁= relative molecular mass of Helium = 4 g/mol
M₂ = relative molecular mass of the gas
Input the value :
Answer:
The correct answer is a scientific law.
Explanation:
The laws of science or scientific laws refer to the statements, which predict or illustrate an array of natural processes. It is a statement based on observations or spontaneous experiments, which illustrate some characteristics of the natural world.
The term law exhibits different uses in various circumstances, that is, across all the branches of natural science. The laws are formulated through data and can be further created via mathematics, in all the conditions, they are indirectly or directly based on empirical evidence. The scientific laws recapitulate the outcomes of observations or experiments, generally within some point of application.
Answer:
Q = 1455.12 Joules.
Explanation:
Given the following data;
Mass = 300 grams
Initial temperature = 22.3
Final temperature = 59.9°C
Specific heat capacity = 0.129 J/gºC.
To find the quantity of energy;
Where,
Q represents the heat capacity.
m represents the mass of an object.
c represents the specific heat capacity of water.
dt represents the change in temperature.
dt represents the change in temperature.
dt = T2 - T1
dt = 59.9 - 22.3
dt = 37.6°C
Substituting the values into the equation, we have;
Q = 1455.12 Joules.
Answer : The concentration of NOBr after 95 s is, 0.013 M
Explanation :
The integrated rate law equation for second order reaction follows:
![k=\frac{1}{t}\left (\frac{1}{[A]}-\frac{1}{[A]_o}\right)](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B1%7D%7Bt%7D%5Cleft%20%28%5Cfrac%7B1%7D%7B%5BA%5D%7D-%5Cfrac%7B1%7D%7B%5BA%5D_o%7D%5Cright%29)
where,
k = rate constant = 
t = time taken = 95 s
[A] = concentration of substance after time 't' = ?
![[A]_o](https://tex.z-dn.net/?f=%5BA%5D_o)
= Initial concentration = 0.86 M
Now put all the given values in above equation, we get:
![0.80=\frac{1}{95}\left (\frac{1}{[A]}-\frac{1}{(0.86)}\right)](https://tex.z-dn.net/?f=0.80%3D%5Cfrac%7B1%7D%7B95%7D%5Cleft%20%28%5Cfrac%7B1%7D%7B%5BA%5D%7D-%5Cfrac%7B1%7D%7B%280.86%29%7D%5Cright%29)
[A] = 0.013 M
Hence, the concentration of NOBr after 95 s is, 0.013 M
