1. Iron fillings are magnetic, so use a magnet to pull the iron fillings out of the mix.
2. Then you can put the salt and sand mixture into water, since salt is soluble, and the salt will dissolve, leaving you with sand.
Atomic mass Ar => 39.948 a.m.u
39.948 g --------------- 6.02x10²³ atoms
?? g -------------------- 3.8x10²⁴ atoms
(3.8x10²⁴) x 39.948 / 6.02x10²³ => 250 g
hope this helps!
I assume you’re looking for a balanced equation.
SiCl4 + 2H2O = SiO2 + 4HCl
Answer:

Explanation:
Hello,
In this case, since the given 5-M concentration of magnesium chloride is expressed as:

We can notice that one mole of salt contains two moles of chloride ions as the subscript of chlorine is two, in such a way, with the volume of solution we obtain the moles of chloride ions as shown below:

Best regards.
Answer:
B. exothermic; leaving
Explanation:
The exothermic process releases heat, which causes the surrounding area to increase in temperature.
Your hand is releasing heat and makes the temperature of the ice cube increase, to where it melts.