Answer: The correct option is C ( is very hard and burns cleanly).
Explanation:
COAL is a form of rock that is made up of mostly carbon amongst other elements which includes sulphur, nitrogen, hydrogen and oxygen. There are different types of coal which include:
--> anthracite ( 90% carbon)
--> bituminous coal ( 70-90% carbon)
--> lignite ( 60- 70% carbon) and
--> peat (60 % carbon).
Anthracite is the type of coal that contains the highest carbon content ( 90% carbon). This makes it very hard and is often a times referred to as HARD COAL. Anthracite is a higher quality coal for domestic and open fire heating. This is because it contains less impurities than other type of coal and thereby making it to BURN CLEANLY avoiding atmospheric pollution.
Explanation:
the conductors are the three u have checked
Answer:
The radioactive isotopes within these brains typically record the ages of the grains-not the time when the sedimentary rock was formed, making it difficult to date using radiometric dating. The half-life of U-235 is 704 million years.
Explanation:
hope this helps but if i'm wrong then i'm sorry..
Answer:
The value of Kc for the reaction is 3.24
Explanation:
A reversible chemical reaction, indicated by a double arrow, occurs in both directions: reagents transforming into products (
direct reaction) and products transforming back into reagents (inverse reaction)
Chemical Equilibrium is the state in which direct and indirect reactions have the same reaction rate. Then taking into account the rate constant of a direct reaction and its inverse the chemical constant Kc is defined.
Being:
aA + bB ⇔ cC + dD
where a, b, c and d are the stoichiometric coefficients, the equilibrium constant with the following equation:
![Kc=\frac{[C]^{c} *[D]^{d} }{[A]^{a} *[B]^{b} }](https://tex.z-dn.net/?f=Kc%3D%5Cfrac%7B%5BC%5D%5E%7Bc%7D%20%2A%5BD%5D%5E%7Bd%7D%20%7D%7B%5BA%5D%5E%7Ba%7D%20%2A%5BB%5D%5E%7Bb%7D%20%7D)
Kc is equal to the multiplication of the concentrations of the products raised to their stoichiometric coefficients divided by the multiplication of the concentrations of the reagents also raised to their stoichiometric coefficients.
Then, in the reaction 3A(g) + 2B(g) ⇔ 2C(g), the constant Kc is:
![Kc=\frac{[C]^{2} }{[A]^{3} *[B]^{2} }](https://tex.z-dn.net/?f=Kc%3D%5Cfrac%7B%5BC%5D%5E%7B2%7D%20%7D%7B%5BA%5D%5E%7B3%7D%20%2A%5BB%5D%5E%7B2%7D%20%7D)
where:
- [A]= 0.855 M
- [B]= 1.23 M
- [C]= 1.75 M
Replacing:

Solving you get:
Kc=3.24
<u><em>The value of Kc for the reaction is 3.24</em></u>
Rust (Fe2O3. 4H2O) is formed when iron interacts slowly with oxygen and water. Mass of Fe in grams is 2.18 x 10⁴ g.
<h3>
What is the explanation?</h3>
There are 2 moles of Fe atoms in 1 mole of Fe2O3-4H2O. The number of moles of Fe atoms in 45.2 kg rust is shown below.
Moles of Fe = 195.01 mol Fe₂O₃.4H₂O (
)
Moles of Fe = 390.02 mol Fe
Multiply the calculated number of moles of iron, Fe, by its molar mass which is 55.85 
Mass of Fe = 390.02 mol Fe (
)
Mass of Fe = 2.18 x 10⁴ g Fe
Avogadro's number (6.022 x 1023) of molecules (or formula units) make up one mole of a substance (ionic compound). The mass of 1 mole of a chemical is indicated by its molar mass. It provides you with the amount of grams per mole of a substance, to put it another way.
To learn more about moles visit:
brainly.com/question/26416088
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