A.
These are characteristics of viruses.
Use the atomic mass of potassium, k, 39.1 g/mol, and the formula n = mass / atomic-mass.
Where n is the number of moles.
n = 250.0 g / 39.1 g/mol = 6.3939 mol.
Now multiply by Avogadro number to find the number of atoms:
6.3939 mol * 6.02*1023 atoms/mol = 38.49 * 10^23 atoms = 3.849 * 10^24.
Answer: 3.85*10^24
<u>Answer:</u>
pH of a KOH solution is 12.73
pOH of a KOH solution is 2.24
pOH of a solution of NaCl is 7
<u>Explanation:</u>
[H+] = ![1.87\times10^-^1^3 M](https://tex.z-dn.net/?f=1.87%5Ctimes10%5E-%5E1%5E3%20M)
According to formula,
![pH=-log[H_3O+]= -log[H+]](https://tex.z-dn.net/?f=pH%3D-log%5BH_3O%2B%5D%3D%20-log%5BH%2B%5D)
= ![- log[1.87\times 10^-^1^3]](https://tex.z-dn.net/?f=-%20log%5B1.87%5Ctimes%2010%5E-%5E1%5E3%5D)
pH=12.73
Then,
![[OH-] = 5.81\times 10^-^3 M](https://tex.z-dn.net/?f=%5BOH-%5D%20%3D%205.81%5Ctimes%2010%5E-%5E3%20M)
According to formula,
pOH=-log[OH-]
= ![- log[5.81\times 10^-^3]](https://tex.z-dn.net/?f=-%20log%5B5.81%5Ctimes%2010%5E-%5E3%5D)
pOH=2.24
Similarly
pH= -log [H+]
= ![- log[1\times10^-^7]](https://tex.z-dn.net/?f=-%20log%5B1%5Ctimes10%5E-%5E7%5D)
pH= 7
Answer:
Empirical formula:
Fe₂O
Subscript of iron in empirical formula is 2.
Explanation:
Empirical formula:
It is the simplest formula that gives the smallest whole number ratio between the atoms of elements present in a compound.
Given data:
Mass of iron = 87.47 g
Mass of oxygen = 12.53 g
Empirical formula = ?
Solution:
Number of gram atoms of iron = 87.47 /55.845 =1.57 grams atoms
Number of gram atoms of oxygen = 12.53 / 16 = 0.78 grams atoms
Atomic ratio:
Fe : O
1.57/0.78 : 0.78/0.78
2 : 1
Fe : O = 2 : 1
Empirical formula:
Fe₂O
Subscript of iron in empirical formula is 2.
Answer:
An objects motion is called kinetic energy. Which is energy that is cause by movement or motion
Explanation: