The combustion reaction is as expressed,
CxHy + O2 --> CO2 + H2O
The mass fraction of carbon in CO2 is 3/11. Hence,
mass of C in CO2 = (3.14 g)(3/11) = 0.86 g C.
Given that we have 1 g of the hydrocarbon, the mass of H is equal to 0.14 g.
moles of C = 0.86 g C / 12 g = 0.0713
moles of H = 0.14 g H / 1 g = 0.14
The empirical formula for the hydrocarbon is therefore, CH₂.
Explanation:
To balance the reactions given, we must understand that the principle to follow is the law of conservation of matter.
Based on this premise, the number of moles of species on the reactant and product side must be the same;
Li + Br₂ → LiBr
Put a,b and c as the coefficient of each species
aLi + bBr₂ → cLiBr
balancing Li;
a = c
balancing Br;
2b = c
let a = 1;
c = 1
b =
or a = 2, b = 1 , c = 2
2Li + Br₂ → 2LiBr
P + Cl₂ → PCl₃
Using the same method;
aP + bCl₂ → cPCl₃
balancing P;
a = c
balancing Cl;
2b = 3c
let a = 1;
c = 1
b =
or
a = 2, b = 3, c = 2
2P + 3Cl₂ → 2PCl₃
iii,
H₂ + SO₂ → H₂S + H₂O
use coefficients a,b,c and d;
aH₂ + bSO₂ → cH₂S + dH₂O
balancing H;
2a = 2c + 2d
balancing S;
b = c
balancing O
2b = d
let b = 1,
c = 1
d = 2
a = 3
3H₂ + SO₂ → H₂S + 2H₂O
Average speed of the trip = 52 km/hr
<h3>Further explanation </h3>
Distance is the length traveled by an object within a certain of time .
Average speed = total distance/total amount of time ,
Can be formulated :
Total distance travelled : 1560 km
Total time : 8 hr + 12 hr + 10 hr = 30 hr
The answer would be 5.5g because you have to subtract 8.2 minus 2.7 and you get 5.5g so basically the answer is C.
For which of the following activities might you want to hire a chemist?
Answer: D. testing a rock sample for gold content
Which of the following procedures involves a physical change in one of the substances?
Answer: C. separating a salt solution by evaporating the water