Answer:
magnesium metal melts = physical change
magnesium metal ignites = chemical change
Explanation:
<em>Physical changes</em> are those in which the identity of the subtance <u>remains unaltered</u>. No new compounds are formed. They involve generally changes in <u>agreggation states of matter</u>: solid, liquid or gas. The first experiment, in which magnesium metal melts is a physical change because it only changes the state of matter, from solid to liquid, but it is still magnesium metal.
Conversely, <em>chemical changes</em> involve atoms combinations to form new compounds. The second experiment, in which magnesium metal ignites, is a chemical change. After the change, magnesium metal is no longer the metal but a metal oxide.
Faster molecules have fewer collisions than slower molecules is True about molecular speed.
<h3>What is Molecular speed?</h3>
Molecular speed refers to the average distance gases or molecules travelled atca particular time rate.
It is valid in ideal gas, where the molecules do not interact with others.
Average molecular speed = Square root (3 (ideal gas constant) * (Temperature)/m)
Therefore, Faster molecules have fewer collisions than slower molecules is True about molecular speed.
Learn more about molecular speed from the link below.
brainly.com/question/14327643
Boiling or also called evaporation is the conversion of liquid to gas through the application of heat. This phase change is an endothermic change and is the opposite of condensation from gas to liquid.
Obsidian - extrusive igneous
granite - clastic sedimentary
conglomerate - intrusive igneous
evaporite - chemical sedimentary
coal - organic sedimentary
marble - metamorphic