Apples turn brown when exposed to air because it undergoes aerial oxidation. Due to this, when the inside of the apple is exposed to the air containing oxygen and water, it turns brown. When apple is uncut, skin of the apple protects it from this process.
If the peeled apple in kept in the refrigerator, the oxidation reaction is greatly slowed down. This is because, rate of chemical reaction decreases with temperature. Hence, in refrigerator it would take several days for it to turn brown.
The complete question is shown in the image attached to this answer.
Answer:
C
Explanation:
Let us quickly remember that the EMF of a cell under non standard conditions in given by the Nernst equation.
This equation states that;
E = E°cell - 0.592/n log Q
Where
E = EMF under non standard conditions
E°cell= standard EMF of the cell
n = number of electrons transferred
Q = reaction quotient
If the reaction quotient is greater than 1 then cell potential is less than the standard cell potential.
The cell that generates the lowest cell potential is the cell depicted in option C because Q has the greatest positive value(Q<1).
N₂ + 3H₂ ⇒ 2NH₃
doesnt matterN₂ + 6.64H₂ ⇒ 2NH₃
(6.64H₂/3H₂) x (2NH₃) =4.4266667
rounded to sig figs= 4.43
<span>C. A completely new substance is formed.</span>
Molar mass:
H₂O = 18.0 g/mol
O₂ = 32.0 g/mol
C₅H₁₂ + 8 O₂ -> 5 CO₂ + 6 H₂<span>O
</span>
8 x (32 g )<span> ------------ 6 x (18 g )</span>
mass O₂ ------------ 108 g H₂O
mass O₂ = 108 x 8 x 32 / 6 x 18
mass O₂ = 27648 / 108
mass O₂ =<span> 256 g</span>
<span>hope this helps!</span>