Answer:
Charge= -2.
Gains two electron into the 4p^4 to become 4p^6.
Explanation:
The element in the periodic table/chart that matches with the valence electron configuration is Selenium with full electron configuration of [Ar] 3d^10 4s^2 4P^4 which is a non-metal that is found in group 4 of the periodic table/chart.
Selenium can receive 2 more electrons on the 4p^4 to give a -2(minus 2) ion that is Se^2-.
Selenium can also loose 2 electron from 4s^2 to give a +2 ion that is Se^2+.
Selenium can also loose 2 electrons from 4s^2 and 2 electrons from 4p^4 to form Se^4+.
Selenium can also loose 2 electrons from 4s^2 and 4 electrons from 4p^4 to form Se^6+.
Thus, in order to form a monatomic ion with a charge(we will be making use of the most stable one). Thus, it will gain two more electron since this is easier to become 4s^2 4p^6.
Homogeneous because everything is mixed together evenly.
27.7g
Explanation:
Given parameters:
Number of moles of oxygen = 3.15moles
Unknown:
Mass of reacting propane = ?
Solution:
Equation of the reaction:
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
We work from the known to the unknown parameters.
The known in this expression is the number of moles of oxygen.
In the reaction:
5 moles of oxygen gas reacts with 1 mole of propane
3.15 mole of oxgen gas will react with 
= 0.63moles
Number of moles of reacting propane gas is 0.63moles
To find the mass;
mass = number of moles x molar mass = 0.63 x molar mass
molar mass of propane = (3 x 12) + (8x1) = 44g/mol
mass of propane = 0.63 x 44 = 27.7g
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Combustion reaction brainly.com/question/6126420
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Answer:
Explanation:
<u>1) Chemical equation (given)</u>
<u>2) Theoretical yield</u>
<u>a) Convert mass of NaHCO₃ to moles:</u>
- n = mass in grams / molar mass
- molar mass = 84.007 g/mol
- n = 2.36 g / 84.007 g/mol = 0.02809 mol
<u>b) Mole ratio:</u>
- 2 mol NaHCO₃ : 1 mol H₂CO₃
<u>c) Proportionality:</u>
- 2 mol NaHCO₃ / mol H₂CO₃ = 0.02809 mol NaHCO₃ / x
⇒ x = 0.2809 / 2 mol H₂CO₃ = 0.01405 mol H₂CO₃
<u>3) Actual yield</u>
<u>a) Mass balance</u>: 2.36 g - 1.57 g = 0.79 g
<u>b) Convert 0.79 g of carbonic acid to number of moles</u>:
- n = mass in grams / molar mass
- n = 0.79 g / 62.03 g/mol = 0.01274 mol
<u>4) Percentage yield, y (%)</u>
- y (%) = actual yield / theoretical yield × 100
- y (%) = 0.1274 mol / 0.1405 mol × 100 = 90.68%
The answer must show 3 significant figures, so y(%) = 90.7%.
Answer:
The correct option is;
D)
Explanation:
The given reaction is presented as follows;
NH₄Cl (s) → NH₃ (g) + HCl (g) ΔH° = 176 kJ/mol, ΔS° = 0.285 kJ/(mol·K)
We note that the Gibbs free energy, ΔG° is represented by the following equation;
ΔG° = ΔH° - T·ΔS°
Where:
T = Temperature (Kelvin)
The reaction will be spontaneous for exergonic reactions, ΔG° < 0 and it will not be spontaneous for endergonic reaction, ΔG° > 0
At room temperature, T = 25 + 273.15 = 298.15 K
Which gives;
ΔG° = 176 - 298.15 × 0.285 = 91.03 kJ/mol which is > 0 Not spontaneous reaction
At 800°C, we have;
T = 273.15 + 800°C + 1073.15 K
ΔG° = 176 - 1073.15 * 0.285 = -129.85 kJ/mol which is < 0 the reaction will be spontaneous
The correct option is therefore, that at room temperature, the reaction is not spontaneous. However, at high temperatures. like 800 °C, the free energy value turns negative and this reaction becomes spontaneous.
