<h3>
Answer:</h3>
0.144 moles
<h3>
Explanation:</h3>
- The relationship between mass of a compound, number of moles and molar mass of the compound is given by;
- Number of moles = Mass ÷ Molar mass
- Molar mass is equivalent to the relative formula mass of the compound that is calculated the atomic masses of the elements making the compound.
In this case;
Our compound, KClO3 will have a molar mass of;
= 39 + 35.5 + 4(16)
= 138.5 g/mol
Mass of KClO3 is 20 g
Therefore;
Number of moles = 20 g ÷ 138.5 g/mol
= 0.144 moles
Thus, the number of moles in 20 g of KClO3 is 0.144 moles
You should read up on Proust's law, better known as the Law of Definite Proportions. This is a chemical law that defines your question more generally, on why the ratio of elements and ions are always fixed.
Basically, this compound Magnesium(II) Chloride is MgCl2 because it has the same number of protons, neutrons, and electrons all the way. This defines the properties of the compound or atom.
The answer is
Physical properties: Properties that do not change the chemical nature of matter
Chemical properties: Properties that do change tha chemical nature of matter
Examples of physical properties are: color, smell, freezing point, boiling point, melting point, infra-red spectrum, attraction (paramagnetic) or repulsion (diamagnetic) to magnets, opacity, viscosity and density. There are many more examples. Note that measuring each of these properties will not alter the basic nature of the substance.
Examples of chemical properties are: heat of combustion, reactivity with water, PH, and electromotive force.
Half life is the time that it takes for half of the original value of some amount of a radioactive element to decay.
We have the following equation representing the half-life decay:
A is the resulting amount after t time
Ao is the initial amount = 50 mg
t= Elapsed time
t half is the half-life of the substance = 14.3 days
We replace the know values into the equation to have an exponential decay function for a 50mg sample
That would be the answer for a)
To know the P-32 remaining after 84 days we have to replace this value in the equation:
So, after 84 days the P-32 remaining will be 0.85 mg
What is the average velocity of atoms in 1.00 mol of argon (a monatomic gas) at 275 k for m, use 0.0399kg
Answer: The average velocity of the atoms 847.33 m/s.
Explanation:
Moles of the neon = 1.00
Temperature of the gas : 288 K
Mass of the gas = 0.01000
R = 8.31 J/mol K
The average velocity of the atoms 847.33 m/s.
