Answer:
The answer to your question is the letter A. 1
Explanation:
Unbalanced chemical reaction
Mg + O₂ ⇒ MgO
Reactants Elements Products
1 Magnesium 1
2 Oxygen 1
Balanced chemical reaction
2Mg + O₂ ⇒ 2MgO
Reactants Elements Products
2 Magnesium 2
2 Oxygen 2
Conclusion
The coefficients of the balanced equation are 2, 1, 2
We need the diagram to answer the question
As a solution is contained with 11% by mass of sodium
chloride, this will therefore conclude that the 100g of the solution is
composed of the 11g of the sodium chloride. In which, the correct answer would
be specified as letter c.
Answer:
0.718L of 0.81M HCl are required
Explanation:
Based on the reaction:
Cd(s)+2HCI(aq) → H2(g)+CdCl2(aq)
<em>1 mol of Cd reacts with 2 moles of HCl</em>
<em />
To solve this question we must, as first, find the moles of Cd. With the moles of Cd we can find the moles of HCl needed to react completely with the Cd. With the moles and the molarity we can find the volume:
<em>Moles Cd -Molar mass: 112.411g/mol-:</em>
32.71g * (1mol / 112.411g) = 0.2910 moles Cd
<em>Moles HCl:</em>
0.2910 moles Cd * (2 moles HCl / 1mol Cd) =
0.5820 moles HCl
<em>Volume:</em>
0.5820 moles HCl * (1L / 0.81moles) =
<h3>0.718L of 0.81M HCl are required</h3>
<span>Answer: option B. 3.07 g
Explanation:
1) given reaction:
S(s) + O₂ (g) → SO(g)
2) Balanced chemical equation:
</span><span>2S(s) + O₂ (g) → 2SO(g)
3) Theoretical mole ratios:
2 mol S : 1 mol O₂ : 2 mol SO
3) number of moles of 4.5 liter SO₂ at</span><span> 300°C and 101 kPa
use the ideal gas equation:
pV = nRT
with V = 4.5 liter
p = 101 kPa
T = 300 + 273.15 K = 573.15 K
R = 8.314 liter×kPa / (mol×K)
=> n = pV / (RT) =
n = [101 kPa × 4.5 liter] / [8.314 (liter×kPa) / (mol×K) × 573.15 K ]
n = 0.0954 mol SO
4) proportion with the theoretical ratio S / SO
2 mol S x
-------------- = ----------------------
2 mol SO 0.0954 mol SO
=> x = 0.0954 mol S.
5) Convert mol of S to grams by using atomic mass of S = 32.065 g/mol
mass = number of moles × atomic mass
mass = 0.0954 mol × 32.065 g/mol = 3.059 g of S
6) Therefore the answer is the option B. 3.07 g
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