Answer:
The natural phenomenon used to describe the length of a meter is the speed of light. The length of a meter is the length a light path travels in 1/(299792458) seconds through a vacuum.
The definition is better due to the uncertainty involved in the use of the length of a standard meter stick because the length of the meter stick could change due to atmospheric conditions from place to place
Explanation:
The correct answer is option 1. Be, Mg, and Ca is the correct order arranged in increasing atomic radius. This is predicted based on the periodic table. The atomic sizes increases as one moves downwards in the periodic table.
Explanation:
4. limestone heat lime + carbon dioxide
The reactants in this expression above is limestone
The products of the reaction is carbon dioxide and lime
Reactant is the species that gives the product and it is usually found on the left hand side of the expression.
The product is the substance on the right hand side of the expression that forms through the experiment.
Heat is used to facilitate the reaction.
5. An exothermic reaction is a reaction in which heat is given off.
An endothermic reaction is a reaction in which heat is absorbed in the process.
An exothermic reaction is always warmer after the reaction whereas an endothermic reaction is colder at the end of the reaction.
Norepinephrine<span> (</span>NE<span>), also called </span>noradrenaline<span> (</span>NA<span>) or </span>noradrenalin<span>, is an </span>organic chemical<span> in the </span>catecholamine<span> family that functions in the </span>brain<span> and </span>body<span> as a </span>hormone<span> and </span>neurotransmitter. The name "noradrenaline," derived from Latin roots meaning "at/alongside the kidneys," is more commonly used in the United Kingdom; in the United States, "norepinephrine," derived from Greek roots having that same meaning, is usually preferred.<span> "Norepinephrine" is also the </span>international nonproprietary name<span> given to the </span>drug.<span>Regardless of which name is used for the substance itself, parts of the body that produce or are affected by it are referred to as </span>noradrenergic<span>.</span>
