Answer:
C,D.
Explanation:
Extrusive, or volcanic, igneous rock is produced when magma exits and cools above (or very near) the Earth's surface. These are the rocks that form at erupting volcanoes and oozing fissures.
Answer:
<u>structural arrangements</u>
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<h2>properties of daimond: </h2><h3>appearance: transparent</h3><h3>hardness: very hard</h3><h3>thermal conductivity :very poor</h3><h3>electric conductivity: poor</h3><h3>density:</h3>
<h3>uses: jewellery and drilling</h3>
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<h2>properties of graphite:</h2>
<h3>appearance: black shiny</h3><h3>hardness: soft ,slippery to touch</h3><h3>thermal conductivity : moderate</h3><h3>electric conductivity: good</h3><h3>density:</h3>
<h3>uses:dry cell, electric arc, pencil lead, lubricant</h3>
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<h2>How Diamond and Graphite are chemically identical?</h2>
- On heating diamond or graphite in the air, they burn completely to form carbon dioxide.
- - Equal quantities of diamond and graphite when burned, produce exactly the same amount of carbon dioxide.
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<h2>Why the physical properties of diamond and graphite are so different?</h2>
Due to the difference in the arrangement of carbon atoms in diamond and graphite
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<h2>
<em><u>hope</u></em><em><u> it</u></em><em><u> helps</u></em><em><u> you</u></em><em><u><</u></em><em><u>3</u></em></h2>
Answer:
[OH⁻] = 4.3 x 10⁻¹¹M in OH⁻ ions.
Explanation:
Assuming the source of the carbonate ion is from a Group IA carbonate salt (e.g.; Na₂CO₃), then 0.115M Na₂CO₃(aq) => 2(0.115)M Na⁺(aq) + 0.115M CO₃²⁻(aq). The 0.115M CO₃²⁻ then reacts with water to give 0.115M carbonic acid; H₂CO₃(aq) in equilibrium with H⁺(aq) and HCO₃⁻(aq) as the 1st ionization step.
Analysis:
H₂CO₃(aq) ⇄ H⁺(aq) + HCO₃⁻(aq); Ka(1) = 4.3 x 10⁻⁷
C(i) 0.115M 0 0
ΔC -x +x +x
C(eq) 0.115M - x x x
≅ 0.115M
Ka(1) = [H⁺(aq)][HCO₃⁻(aq)]/[H₂CO₃(aq)] = [(x)(x)/(0.115)]M = [x²/0.115]M
= 4.3 x 10⁻⁷ => x = [H⁺(aq)]₁ = SqrRt(4.3 x 10⁻⁷ · 0.115)M = 2.32 x 10⁻⁴M in H⁺ ions.
In general, it is assumed that all of the hydronium ion comes from the 1st ionization step as adding 10⁻¹¹ to 10⁻⁷ would be an insignificant change in H⁺ ion concentration. Therefore, using 2.32 x 10⁻⁴M in H⁺ ion concentration, the hydroxide ion concentration is then calculated from
[H⁺][OH⁻] = Kw => [OH⁻] = (1 x 10⁻¹⁴/2.32 x 10⁻⁴)M = 4.3 x 10⁻¹¹M in OH⁻ ions.
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NOTE: The 2.32 x 10⁻⁴M value for [H⁺] is reasonable for carbonic acid solution with pH ≅ 3.5 - 4.0.
The anode is the negative electrode and so will be donating electrons to assist in this chemical reaction occuring. All reactions accept electrons as reactants. The key issue is the reduction potential Eo (+1.8V). This is greatest for the reaction:
Co3+ + e -> Co2+
Therefore this reaction has the greatest tendency to occur.
Answer:
The total pressure is 0,804 atm
Explanation:
We use Dalton's law according to which the sum of the partial pressures is equal to the total pressure of a gas mixture. We convert the pressure in Pascals to atmosphere (it can also be done in reverse):
101300Pa ----1 atm
4500Pa----x= (4500Pa x 1atm)/101300Pa= 0,044 atm
P total= p1 + p2= 0,76 atm + 0,044 atm=0,804 atm
