A chemical change is characterized of the formation of new substances or a chemical reaction. There are a number of observations that we can see if this type of change happens. One would be the formation of gas bubbles, this indicates that one of the products is a gas. Another observation would be a formation of a precipitate in the solution, it would indicate that the new solid formed is not soluble in the solution. A permanent color change in the solution would also indicate a chemical change because it may be that the new substance that is formed has its own distinct color when in solution.
Answer:
Concave Lenses Are for the Nearsighted, Convex for the Farsighted. Concave lenses are used in eyeglasses that correct nearsightedness.
Explanation:
The endocrine system<span> is the collection of </span>glands<span> of an organism that </span>secrete hormones<span>directly into the </span>circulatory system<span>to be carried towards distant target organs. In </span>humans<span>, the major </span>endocrine glands<span> include the </span>pineal gland<span>, </span>pituitary gland<span>, </span>pancreas<span>, </span>ovaries<span>, </span>testes<span>, </span>thyroid gland<span>, </span>parathyroid gland<span>, and </span>adrenal glands<span>. In </span>vertebrates<span>, the </span>hypothalamus<span> is the neural control center for all endocrine systems. The field of study dealing with the endocrine system and its disorders is </span>endocrinology<span>, a branch of </span>internal medicine.<span>
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