Answer:
The basic steps of the scientific method are: 1) make an observation that describes a problem, 2) create a hypothesis, 3) test the hypothesis, and 4) draw conclusions and refine the hypothesis.
Answer:
You have got the Combined Gas Equation for an Ideal Gas, which holds that
P
1
V
1
T
1
=
P
2
V
2
T
2
V
2
=
P
1
×
V
1
×
T
2
T
1
×
P
2
...
Explanation:
Answer : The value of rate constant is, 
Explanation :
First we have to calculate the rate constant, we use the formula :
Expression for rate law for first order kinetics is given by:

where,
k = rate constant = ?
t = time passed by the sample = 20 min
a = let initial amount of the reactant = 100 g
a - x = amount left after decay process = 100 - 85 = 15 g
Now put all the given values in above equation, we get


Therefore, the value of rate constant is, 
Answer:
- The percentage of unit cell volume that is occupied by atoms in a face- centered cubic lattice is 74.05%
- The percentage of unit cell volume that is occupied by atoms in a body-centered cubic lattice is 68.03%
- The percentage of unit cell volume that is occupied by atoms in a diamond lattice is 34.01%
Explanation:
The percentage of unit cell volume = Volume of atoms/Volume of unit cell
Volume of sphere = 
a) Percentage of unit cell volume occupied by atoms in face- centered cubic lattice:
let the side of each cube = a
Volume of unit cell = Volume of cube = a³
Radius of atoms = 
Volume of each atom =
= 
Number of atoms/unit cell = 4
Total volume of the atoms = 
The percentage of unit cell volume =
= 0.7405
= 0.7405 X 100% = 74.05%
b) Percentage of unit cell volume occupied by atoms in a body-centered cubic lattice
Radius of atoms = 
Volume of each atom =
=
Number of atoms/unit cell = 2
Total volume of the atoms = 
The percentage of unit cell volume =
= 0.6803
= 0.6803 X 100% = 68.03%
c) Percentage of unit cell volume occupied by atoms in a diamond lattice
Radius of atoms = 
Volume of each atom =
= 
Number of atoms/unit cell = 8
Total volume of the atoms = 
The percentage of unit cell volume =
= 0.3401
= 0.3401 X 100% = 34.01%