Always remember that a compound can be separated into simpler substances by chemical methods/reactions. While elements cannot be broken down into simpler substances by chemical reactions. You can do a flame test and spectrum analysis to determine whether a solid material is an element or a compound. Check the boiling and/or melting point, color or density. Also check the solid material’s reaction with oxygen, hydrogen, calcium, or various acids. Examine and study its physical chemistry. The element(s) that may be present may be identified by checking the absorption edges from an x-ray spectrum.
The crest is cover distance. <span>The </span>speed<span> of a wave indicate how fast wave is moving. </span>T<span>he speed is the distance traveled by a crest in a given interval of time. Greater distance in same amount of time means wave travel faster.
speed of wave = distance/time.
speed of wave = 0,2 m </span>÷ 0,2 s = 1 m/s.
viruses are made of proteins and contain genetic information to produce more of them in the form of DNA or RNA.
It is true that substances that have a high melting point and conduct electricity in the liquid phase are ionic substances, and if one of your options is NaCl, then that is the correct answer.