The wax can melt and just maybe make another part of the candle
Answer: 0.8g/cm^3
Explanation:
In seeing your problem, I see an issue with your units for centimeter. The volume is in the third dimension, so we use cm^3 every single time for the volume. That way, we can arrive to the correct density (in g/cm^3)
Density = mass/volume and so
Density = 8g/10cm^3
= 0.8g/cm^3
Answer:
a) 0.13 bar
b) 5.05 L
Explanation:
Let us take the mass of the mixture to be 100 g. Hence, 70% by weight of dioxygen corresponds to 70 g
Mass of dihydrogen = 100g - 70 g = 30g
Number of moles of dioxygen = 70g/32 g/mol = 2.2 moles of dioxygen
Number of moles of dihydrogen = 30g/2g/mol = 15 moles of dihydrogen
Total number of moles = 2.2 + 15 = 17.2 moles
Mole fraction of dioxygen = 2.2/17.2 = 0.13
Partial pressure = mole fraction * total pressure
Partial pressure of dioxygen = 0.13 * 1 = 0.13 bar
ii) number of moles in 8.8 g of CO2 = 8.8g/44g/mol = 0.2 moles
T = 31.1 + 273 = 304.1 K
P = 1 bar
V= ?
R = 0.083 bar L K-1 mol-1
From
PV=nRT
V = nRT/P
V= 0.2 * 0.083 * 304.1/1
V= 5.05 L
From the combustion of octane, the formaldehyde will be formed as this equation:
C8H18 + O2 → CH2O + H2O this is the original equation but it is not a balanced equation, so let's start to balance it:
the equation to be balanced so the number of atoms on the right side of the equation sholud be equal with the number of atoms on the lef side.
-we have 8 C atoms on left side and 1 atom on the right side so we will try putting 8 CH2O on the right side instead of CH2O
C8H18 + O2 → 8 CH2O + H2O
we have 2 O atoms on the left side and 9 atoms on the right side so we will try first to put 9 O2 instead of O2 on the left side and put 2H2O on the right side and put 16 CH2O instead of 8 CH2O to make the atoms of O are equal on both sides = 18 atoms
C8H18 + 9 O2 → 16 CH2O + 2H2O
put now we have 8 atom C on the left side and 16 atom on the right side so, we will put 2 C8H18 instead of C8H18 now we get this equation:
2C8H18 + 9O2 →16 CH2O + 2H2O
-now we have 36 of H atoms on both sides.
- and 16 of C atoms on both sides.
- and 18 of O atoms on both sides.
now all the number of atoms of O & C & H are equal on both sides
∴ 2C8H18 + 9O2 → 16 CH2O + 2 H2O
is the final balanced equation for the formation of formaldehayde
When we say STP that means the system is at its standard temperature and pressure. Both systems is having the same condition hence temperature and pressure is constant. We then set the amount of gas in both cases to be equal. Hence from the ideal gas law,
PV=nRT we can say that with everything constant, volume must also be constant.
The answer is (2) 2 L of methane gas.