Hey there!
MgCl₂
Find molar mass of magnesium chloride.
Mg: 1 x 24.305
Cl: 2 x 35.453
--------------------
95.211 grams
One mole of magnesium chloride has a mass of 95.211 grams.
We have 2.40 moles.
2.40 x 95.211 = 228.5
To 3 sig figs this is 229.
The mass of 2.40 moles of magnesium chloride is 229 grams.
Hope this helps!
Freeze drying<span> (or lyophilization) removes water from the ice cream by lowering the </span>air pressure<span> to a point where ice sublimates from a </span>solid<span> to a </span>gas<span>. The ice cream is placed in a </span>vacuum chamber<span> and frozen until the water </span>crystallizes<span>. The air pressure is lowered, creating a partial vacuum, forcing air out of the chamber; next heat is applied, </span>sublimating<span> the ice; finally a freezing coil traps the vaporized water. This process continues for hours, resulting in a freeze-dried ice cream slice. </span>
Atomic mass Calcium ( Ca) = 40.078 u.m.a
40.078 g --------------- 6.02x10²³ atoms
187 g ------------------- ??
187 x ( 6.02x10²³) / 40.078 =
1.125x10²⁶ / 40.078 = 2.808x10²⁴ atoms
hope this helps!
Answer:
A. Condensation
B. Evaporation
Explanation:
Condensation releases energy when water vapor condenses to form water droplets. Evaporation absorbs energy whenever it changes from liquid to gas, the heat from the sun heats the water up and absorbs energy.
