Answer:

Explanation:
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In this case, considering the given chemical reaction and the mass of the magnesium strip, following the indications of the atomic weight ratio (2.61 g Cu/1 g Mg), and keeping in mind the 1:1 mole ratio one could compute the produced mass of copper as shown below:

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The following of what exactly?
Answer:
Two
Explanation:
The law of conservation of mass states that in an isolated system the mass present is neither destroyed nor created by chemical changes or physical changes.
This tells us that the mass of reactants must be equal to the product mass.
If 1 atom of Zn react with one atoms of sulfur, the product will be 1 molecule of zinc sulfide according to the equation below
Zn(s) + S(s) ⇒ ZnS(s)
therefore two atoms each f zinc and sulfur will product two molecules of Zn sulfide
Answer: D. They are made up of hard spheres that are in random motion.
Explanation:
A gas is a <u>state of aggregation of matter</u> in which, under certain conditions of temperature and pressure, <u>its molecules interact weakly with each other, without forming molecular bonds</u>, adopting the shape and volume of the container that contains them and tending to separate everything possible because of its <u>high concentration of kinetic energy</u>.
The molecules of a gas are practically <u>free</u> and have the ability to be distributed throughout the space in which they are contained because <u>the gravitational forces and attraction between them are practically negligible</u> compared to the speed at which they move. .
Therefore, gas molecules do not travel specific trajectories or vibrate in a stationary position, instead <u>they move quickly and randomly through the entire space of the container that contains them.</u>