4. A
because PbCl2 is an ionic compound and it's solid, so it's a substance.
It cannot be mixture, because it's a pure molecule.
5. D
despite that both substances are gases, colorless they are different molecules, so they should have different either chemical and physical properties
6. C
this substance made from W atoms and others are made from molecules
The balanced chemical reaction is:<span>
</span><span>2C6H6 + 15O2 → 12CO2 + 6H2O</span><span>
We
are given the amount of carbon dioxide to be produced for the reaction. This will
be the starting point of our calculations.
</span>42 g CO2 ( 1 mol CO2 / 44.01 g CO2) ( 2 mol C6H6 / 12 mol CO2 ) (78.1074 g C6H6 / 1 mol C6H6) = 12.42 grams of C6H6
Answer:
Helium has atomic mass 4.002602.
So the answer to yr question is helium.
Answer:
whah the other dude said :) also stay safe
Explanation:
☀️
Molar mass of 
<u>As we know</u>–
1 mol =
formula units
1 mol = 143.092 g = formula units
Henceforth –
formula units –
