Answer:
Explanation:
A pure substance is made up solely of that substance and can't be separated into any other substances. A mixture can be separated into two or more pure substances
Answer:
Yes
Explanation:
The speed of light is about 300 000 km per second, so light takes about 1.28 seconds to travel from the Moon to the Earth.
The concentration of AlCl3 solution if 150 ml of the solution contains 550 mg of cl- ion is 0.0344 M
calculation
concentration = moles /volume in liters
volume in liters = 150 /1000= 0.15 L
number of moles calculation
write the equation for dissociation of Al2Cl3
that is AlCl3 ⇔ Al^3+ + 3 Cl ^-
find the moles of Cl^- formed
moles =mass/molar mass
mass in grams= 550/ 1000 =0.55 grams
molar mass of Cl^- =35.5 g/mol
moles is therefore= 0.55/35.5 =0.0155 moles
by use of mole ration betweem AlCl3 to Cl^- which is 1:3 the moles of AlCl3 is =0.0155 x 1/3= 5.167 x10^-3 moles
concentration of AlCl3 is therefore= 5.167 x10^-3/ 0.15 =0.0344 M
Answer:
He
Explanation:
A molecule is the smallest physical unit of a substance that can exist independently, consisting of 2 or more atoms chemically combined
He is one atom of Helium