Answer:
Mass = 8 g
Explanation:
Given data:
Mass of MgO formed = 20 g
Mass of oxygen needed = ?
Solution:
Chemical equation:
2Mg + O₂ → 2MgO
Number of moles of MgO:
Number of moles = mass/molar mass
Number of moles = 20 g/ 40 g/mol
Number of moles = 0.5 mol
Now we will compare the moles of MgO and O₂ from balance chemical equation:
MgO : O₂
2 : 1
0.5 : 1/2×0.5 = 0.25 mol
Mass of oxygen required:
Mass = number of moles × molar mass
Molar mass of O₂ is 32 g/mol
Mass = 0.25 mol × 32 g/mol
Mass = 8 g
More water is not always better. For example; cacti only need water about every two weeks, the same with succulent plants. Not every plant needs to be watered every day, or the plant may be overwatered and die.
Answer:
6,04x10⁻³M
Explanation:
For the reaction:
Fe(s) + CuSO₄(aq) → Cu(s) + FeSO₄(aq)
The precipitate of Cu(s) weights 96,0 mg. In moles:
Moles of Cu(s):
0,096g×(1mol/63,546g) = 1,51x10⁻³ moles of Cu(s). If you see the balanced equation 1 mole of CuSO₄ produce 1 mole of Cu(s). That means moles of CuSO₄ are the same of Cu(s), <em>1,51x10⁻³ moles of CuSO₄</em>
As volume of the solution is 250 mL, 0,250L, the molar concentration of the original solution is:
1,51x10⁻³ moles of CuSO₄ / 0,250L = <em>6,04x10⁻³M</em>
I hope it helps!
Answer:
See explanation
Explanation:
Racemization is said to occur when a 1:1 ratio of (+) and (-) enantiomers of a compound are produced in a reaction.
The reaction of optically active (R)-2-methylcyclohexanone with either aqueous base or acid leads to the formation of a planar enol species for reaction with acid and a planar enolate species for reaction with base.
Both reactions involves the formation of achiral species which reverts back to the chiral product with equal chances of the formation of both enantiomers of the product during the process. This leads to racemization of the product in both cases.