There are 7 periods in the modern periodic table
Answer:
Explanation:
To separate the a mixture of chalk and potassium chloride, we must not that chalk is calcium carbonate compound, CaCO₃.
Calcium carbonate has low solubility in water. KCl is readily soluble in water and it is also an ionic compound.
To separate a mixture of compounds with various solubility, we can carryout dissolution, filtration and evaporation.
We first pour pure water into the mixture. Water will dissolve the potassium chloride readily.
Then using a filter paper we filter out the suspended chalk particles. Leave the filtrate to then dry and collect it.
The solution filtered should be evaporated to dryness. This will leave the KCl behind from the solution.
The cause of no gravity means the effect will be we float.
Answer:
1.0555 * 10^24 molecules
Explanation:
Number of molecules = ?
Mass = 3.79 Kg = 3790 g
Molar mass of Cs7(Cr5O3)4 = 2162.25 g/mol
Number of moles = Mass / Molar mass
Number of moles = 3790 g / 2162.25 g/mol
Number of moles = 1.7528 mol
1 mol = 6.022 * 10^23 molecules
1.7528 mol = x
solving for x;
x = 6.022 * 10^23 * 1.7528
x = 1.0555 * 10^24 molecules
