An oxygen gas is a diatomic molecule which means that each molecule is composed of 2 atoms. Its symbol is O2.
Each oxygen atom has a molar mass of 16 g/mol. The molar mass of oxygen gas is calculated below,
molar mass = 2 x (16 g/mol) = 32 g/mol
To determine the number of moles in 52.5 grams of oxygen, divide the given mass by the calculated molar mass.
n = 52.5 grams / (32 gram/ mol)
n = 1.64 moles
Thus, there are 1.64 moles of oxygen gas.
Answer:
Carbon atoms in graphite and diamond are arranged in different ways. Hence, the two allotropes of carbon have different physical properties.
Explanation:
Both graphite and diamond are both made of only carbon atoms. However, their physical properties differ from each other. Hence, they are called allotropes. Think about how these carbon atoms are arranged in each of the allotropes.
<h3>Graphite</h3>
In graphite, each carbon atom is bonded to three other carbon atoms. These carbon atoms will be located in the same plane. A chunk of graphite can contain many of these planes.
Each carbon atom has four valence electrons. Three of these electrons will be used in the bonds. The other electron will be delocalized. These electrons would flow between the sheets of carbon atoms. That keeps the sheets separate and allow them to slide on top of each other.
<h3>Diamond</h3>
In diamond, each carbon atom is bonded to four other carbon atoms. These carbon atoms will form a tetrahedral network.
In graphite, there's a significant separation between two adjacent sheets of carbon atoms. The force between the two sheets is rather weak. When a piece of graphite is between two objects that move over one another, the layers in the graphite would also slide over one another. Since the attraction between two adjacent sheets isn't very strong, there wouldn't be much resistance. Hence the graphite acts as a lubricant.
In contrast, most of the carbon atoms in a piece of diamond would be connected to each other. Unlike the sheets in graphite, in a diamond there are almost no moving parts. Also, the forces between neighboring carbon atoms are very strong. When an external force acts on a chunk of diamond, the carbon atoms would barely move. Hence, the structure appears to be very rigid. That gives diamond its abrasive properties.
Answer:
Depends, but in most cases, 2.
It's best to use as many digits as possible to keep it accurate.
Explanation:
This varies between teachers, as most schools go with 2 decimal places.
This is something that depends in your situation.
You technically want as many decimals as possible to keep it as accurate, but most people stick with 2.
I personally do 3, and commonly do 5 sometimes.
Half-life is basically how long it takes for a radioactive molecule to get to 1/2 of its original mass.
so if sodium 24 mass was 5g and it's half life was 24years then:
after every 24years 1/2 of 5g would have decayed. so in 48years there will only be 2.5g left.