Explanation and answer:
The molar volume of a gas is 22.4 L at 0 deg. C.
So the molar mass of the gas is, by proportion,
0.16 g * (22400 mL)/(240 mL) = 14.93 g
The molar mass of (CH4)n = 12+4(1) = 16.
So n = 15.93/16 = 1, or the molecular formula is CH4.
Note: The temperature at which the volume was observed was not given. If 240 cm^3 was observed at 20 deg.C, then the volume at 0 deg.C would be
V=240*(273+0)/(273+20) = 223.6
The molar mass = 0.16*22400/(223.6) = 16.03
which gives n = 16/16.03 = 1 again, but more accurately.
halogens
Group 7A (or VIIA) of the periodic table are the halogens: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).
Answer:
.........................................
Explanation:
From the given equations, the combustion reaction is;
C₄H₁₂ + 7O₂ --> 4CO₂ + 6H₂O
Combustion reactions are when organic compounds react with O₂ to produce water and CO₂. From the given reactions, C₄H₁₂ is an organic compound that reacts with O₂ to produce water and CO₂.
Therefore this is the only reaction that follows the general equation for combustion.
Answer:
MgBr₂
Explanation:
Here we need to find the molar proportions of the two elements which will give us the empirical formula of the compound. To do that,we need to determine the number of moles the grams given represent, and then convert them to whole numbers to find their proportions.
Atomic weght Br = 79.904 g/mol mol
⇒ mol Br = 32.0 g/ 79.904 g/mol = 0.40 mol
Atomic weight Mg = 24.305 g/mol
⇒ mol Mg = 4.9 g/24.305 g/mol = 0.20 mol
Their proportions are
0.40 Br ÷ 0.20 Mg = 2 Br ÷ 1 Mg
Empirical formula = MgBr₂