Answer:
The answer to your question is A.
Pure substances can not be broken down into others, so they cannot be molecules
Explanation:
Answer:

Explanation:
Hello!
In this case, since the molarity of magnesium chloride (molar mass = 95.211 g/mol) is 1.672 mol/L and we know the density of the solution, we can first compute the concentration in g/L as shown below:
![[MgCl_2]=1.672\frac{molMgCl_2}{L}*\frac{95.211gMgCl_2}{1molMgCl_2}=159.2\frac{gMgCl_2}{L}](https://tex.z-dn.net/?f=%5BMgCl_2%5D%3D1.672%5Cfrac%7BmolMgCl_2%7D%7BL%7D%2A%5Cfrac%7B95.211gMgCl_2%7D%7B1molMgCl_2%7D%3D159.2%5Cfrac%7BgMgCl_2%7D%7BL%7D)
Next, since the density of the solution is 1.137 g/mL, we can compute the concentration in g/g as shown below:
![[MgCl_2]=159.2\frac{gMgCl_2}{L}*\frac{1L}{1000mL}*\frac{1mL}{1.137g}=0.14](https://tex.z-dn.net/?f=%5BMgCl_2%5D%3D159.2%5Cfrac%7BgMgCl_2%7D%7BL%7D%2A%5Cfrac%7B1L%7D%7B1000mL%7D%2A%5Cfrac%7B1mL%7D%7B1.137g%7D%3D0.14)
Which is also the by-mass fraction and in percent it turns out:

Best regards!
n = 1.5atm (15L) / .0821 (280k) = .98 mol NaCl
NaCl = 22.99g Na + 35.45g Cl = 58.44g NaCl
58.44g NaCl x .98 mol NaCl = 57.27g NaCl
Explanation:
hope you get it right :)
A change in temperature is a sign that a chemical reaction has occurred. This occurs in an endothermic reaction. An endothermic process is any process which requires or absorbs energy from its surroundings, usually in the form of heat. It may be a chemical process, such as dissolving ammonium nitrate in water, or simply the melting of ice cubes.
Hopefully im not too late :/