Answer:
Option (C)
Explanation:
The O horizon is the top layer of the soil, which occurs as both thick and thin soil at different places, and it is absent in certain places. It is comprised of organic matter which mainly includes the decomposed leaves and also sometimes, the dead remains of animals are also found which enhances the quality of the soil. This layer is also known as the humus or organic layer.
Thus, the correct answer is option (C).
1. The molar mass of Fe2(CO3)3 is 291.72 g/mol. This means that 45.6 g is equivalent to 0.156 mol. Dividing by the 0.167 L of water gives a solution of 0.936 M.
2. Multiplying (0.672 M)(0.025 L) = 0.0168 mol. The molar mass of Ni(OH)2 is 92.71 g/mol, so multiplying by 0.0168 mol = 1.56 grams. Therefore you would need to dissolved 1.56 g of Ni(OH)2 into 25 mL of water.
3. Fe2(CO3)3 + Ni(OH)2 --> Fe(OH)3 + NiCO3Balancing: Fe2(CO3)3 + 3Ni(OH)2 --> 2Fe(OH)3 + 3NiCO3The reaction quotient is:[Fe(OH)3]^2 * [NiCO3]^3 / [Fe2(CO3)3][Ni(OH)2]^3= (0.05)^2 * (1.45)^3 / (0.936)(0.672)^3= 0.0268Since this is < 1, it implies that the reactants are favored at equilibrium.
Answer:
Rate constant at 725 K is 
Explanation:
According to Arrhenius equation for a reaction-

where
and
are rate constants of reaction at
and
temperatures (in kelvin) respectively.
is activation energy of reaction.
Here
= 600 K ,
= 
= 725 K,
= 262 kJ/mol and R = 8.314 J/(mol.K)
So plugin all the values in the above equation-

So,
= 
Hence rate constant at 725 K is 
2. B) electrical chemical thermal mechanical
3. B) light, sound, and heat
4. A) light energy from the sun
Answer:
Aluminium is a highly reactive metal yet it is used to make utensils for cooking this is because aluminium reacts with oxygen present in air to form a thin layer of Aluminium oxide is oxide layer is very stable and prevent for the reaction of aluminium with oxygen