Answer:
The correct option is B. Activation energy
Explanation:
The activation energy is usually used to designate the minimum energy necessary for a given chemical reaction to occur, that is, the basic requirement for the reaction to proceed.
For a reaction to occur between two molecules, they must collide in the correct orientation and have a minimum amount of energy. As the molecules approach, their electron clouds are rejected. This requires energy (activation energy) and comes from the heat of the system, that, is, from translational, vibrational energy, etc of each molecule. If the energy is sufficient, the repulsion is overcome and the molecules are close enough for a rearrangement of the bonds of the molecules.
The concept of Activation energy was introduced by Arrhenius in 1889. Arrhenius suggested that molecules must prossess a minimum amount of energy to react. That energy comes from the kinetic energy of the clliding molecules. Kinetic energy serves to cause reactions, but if the molecules move very slowly, the molecules will only bounce when they collide with other molecules and the reaction does not happen. In order for the molecules to react, they must have a total kinetic energy that is equal to or greater than a certain minimum value of energy called activation energy.
Answer:
Soil erosion.
Explanation:
No-till plowing can be defined as a farming method or technique which typically involves planting crops (seedlings) without tilling the soil rather the farmer would only open a narrow or very shallow trench of sufficient depth and width to cover up the seedlings. Thus, the no-till plowing makes crop residues to be left on the soil and by extension preventing soil erosion through the absorption of water by the crop residues.
Hence, by leaving crop roots in the ground and stalks on the surface, no-till plowing helps prevent soil erosion.
Additionally, the water retention ability of no-till plowing is usually a boon to farmers because it slows down evaporation and serves as a good protection for drought-stricken environments.
Answer:
The double helix is the description of the structure of a DNA molecule. A DNA molecule consists of two strands that wind around each other like a spiral staircase. Each chain has a backbone in which a sugar (deoxyribose) and a phosphate group alternate.
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the pituitary gland is situated in "the Turkish saddle" connected to the hypothalamus by the hypothalamo-hypophyseal portal system and hypothalamo-hypophyseal tract.
the pineal gland is located within the diencephalon